1 2Bristol Emulations 3------------------ 4 5This is a write-up of each of the emulated synthesisers. The algorithms 6employed were 'gleaned' from a variety of sources including the original 7owners manuals, so they may be a better source of information. The author 8has owned and used a selection but far from all of the originals. Some of them 9were built just from descriptions of their operation, or from understanding 10how synths work - most of them were based on the Mini Moog anyway. Many of 11the synths share components: the filter covers most of them, the Prophets and 12Oberheims share a common oscillator and the same LFO is used in many of them. 13Having said that each one differs considerably in the resulting sound that is 14generated, more so than initially expected. Each release refines each of the 15components and the result is that all emulations benefit from the improvements. 16All the emulations have distinctive sounds, not least due to that the original 17instruments used different modulations and mod routing. 18The filter, which is a large defining factor in the tonal qualities of any 19synth, is common to all the emulations. The filter implements a few different 20algorithms and these do separate each of the synths: the Explorer layering 21two low pass filters on top of each other: the OB-Xa using different types 22depending on 'Pole' selection. Since release 0.20.8 the emulator has had a 23Houvillainen non-linear ladder filter integrated which massively improves 24the quality at considerable expense to the CPU. 25There is one further filter algorithm used solely for the Leslie rotary 26emulator crossover, this is a butterworth type filter. 27 28Bristol is in no way related to any of the original manufacturers whose 29products are emulated by the engine and represented by the user interface, 30bristol does not suggest that the emulation is a like representation of the 31original instrument, and the author maintains that if you want the original 32sound then you are advised to seek out the original product. Alternatively a 33number of the original manufacturers now provide their own vintage collections 34which are anticipated to be more authentic. All names and trademarks used by 35Bristol are ownership of the respective companies and it is not inteded to 36misappropriate their use here. If you have concerns you are kindly requested 37to contact the author. 38 39The write-up includes the parameter operations, modulations, a description of 40the original instrument and a brief list of the kind of sounds you can expect 41by describing a few of the well known users of the synth. 42 43Several emulations have not been written up. Since the APR 2600 was implemented 44it became a rather large job to actually describe what was going on. If you 45really want to know about the synths that are not in this document then you 46might want to search for their owners manuals. 47 48All emulations are available from the same engine, just launch multiple GUIs 49and adjust the midi channels for multi timbrality and layering. 50 51It is noted here that the engine is relatively 'dumb'. Ok, it generates a very 52broad range of sounds, currently about 25 different synthesisers and organs, 53but it is not really intelligent. Memories are a part of the GUI specification 54- it tells the engine which algorithm to use on which MIDI channel, then it 55calls a memory routine that configures all the GUI controllers and a side effect 56of setting the controllers is that their values are sent to the engine. This is 57arguably the correct model but it can affect the use of MIDI master keyboards. 58The reason is that the GUI is really just a master keyboard for the engine and 59drives it with MIDI SYSEX messages over TCP sessions. If you were to alter the 60keyboard transpose, for example, this would result in the GUI sending different 61'key' numbers to the engine when you press a note. If you were already driving 62the synth from a master keyboard then the transpose button in the Brighton GUI 63would have no effect - the master keyboard would have to be transposed instead. 64This apparent anomaly is exacerbated by the fact that some parameters still are 65in the engine, for example master tuning is in the engine for the pure fact that 66MIDI does not have a very good concept of master tuning (only autotuning). 67Irrespective of this, bristol is a synthesiser so it needs to be played, 68tweaked, driven. If you think that any of the behaviour is anomalous then let 69me know. One known issue in this area is that if you press a key, transpose 70the GUI, then release the key - it will not go off in the engine since the GUI 71sends a different key code for the note off event - the transposed key. This 72cannot be related to the original keypress. This could be fixed with a MIDI all 73notes off event on 'transpose', but I don't like them. Also, since the 0.20 74stream the problem only affects a few of the emulations, the rest now sending 75a transpose message to the engine and letting it do the work. 76 77Since release 0.30.6 the engine correctly implements monophonic note logic. 78Prior to this the whole engine was polyphonic and playing with one voice only 79gave last note preference which dramatically affects playing styles - none of 80the cool legato effects of the early monophonics. The quoted release fix this 81limitation where the engine will keep a keymap of all played keys (one per 82emulation) when started with a single voice and uses this map to provide 83consistent note precedence, high note logic, low note logic or just using the 84previously implemented last note logic. In this release the keymap was only 85maintained with monophonic emulations, this is a potential extension as even 86in polyphonic mode it would be useful for arpeggiation (which is currently 87implemented using a FIFO rather than an ordered keymap). 88 89 90 91 92 Moog Mini 93 --------- 94 95It is perhaps not possible to write up who used this synth, the list is endless. 96Popular as it was about the first non-modular synthesiser, built as a fixed 97configuration of the racked or modular predecessors. 98 99Best known at the time on Pink Floyd 'Dark Side of the Moon' and other albums. 100Rick Wakeman used it as did Jean Michel Jarre. Wakefield could actually 101predict the sound it would make by just looking at the settings, nice to be 102able to do if a little unproductive but it went to show how this was treated 103as an instrument in its own right. It takes a bit of work to get the same sweet, 104rich sounds out of the emulation, but it can be done with suitable tweaking. 105 106The original was monophonic, although a polyphonic version was eventually made 107after Moog sold the company - the MultiMoog. This emulation is more comparable 108to that model as the sound is a bit thinner and can be polyphonic. The design 109of this synth became the pole bearer for the following generations: it had 110three oscillators, one of which could become a low frequency modulator. They 111were fed into a mixer with a noise source, and were then fed into a filter 112with 2 envelope generators to contour the wave. Modulation capabilities were 113not extensive, but interestingly enough it did have a frequency modulation (FM) 114capability, eventually used by Yamaha to revolutionise the synthesiser market 115starting the downfall of analogue synthesis twenty years later. 116 117All the analogue synths were temperature sensitive. It was not unusual for the 118synths to 'detune' between sound test and performance as the evening set in. 119To overcome this they could optionally produce a stable A-440Hz signal for 120tuning the oscillators manually - eventually being an automated option in the 121newer synths. Whilst this digital version has stable frequency generation the 122A-440 is still employed here for the sake of it. 123 124Modifiers and mod routing are relatively simple, Osc-3 and noise can be mixed, 125and this signal routed to the oscillator 1 and 2 frequency or filter cutoff. 126 127The synth had 5 main stages as follows: 128 129Control: 130 131 Master tuning: up/down one note. 132 133 Glide: (glissando, portamento). The rate at which one key will change its 134 frequency to the next played key, 0 to 30 seconds. 135 136 Mod: source changes between Osc-3 and noise. 137 138 Release: The envelope generators had only 3 parameters. This governed whether 139 a key would release immediately or would use Decay to die out. 140 141 Multi: Controls whether the envelope will retrigger for each new keypress. 142 143Oscillators: 144 145 There are three oscillators. One and two are keyboard tracking, the third 146 can be decoupled and used as an LFO modulation source. 147 148 Oscillator 1: 149 Octave step from 32' to 1'. 150 Waveform selection: sine/square/pulse/ramp/tri/splitramp 151 Mod: controls whether Osc-3/noise modulates frequency 152 153 Oscillator 2: 154 Octave step from 32' to 1'. 155 Fine tune up/down 7 half notes. 156 Waveform selection: sine/square/pulse/ramp/tri/splitramp 157 Mod: controls whether Osc-3/noise modulates frequency 158 159 Oscillator 3: 160 Octave step from 32' to 1'. 161 Fine tune up/down 7 half notes. 162 Waveform selection: sine/square/pulse/ramp/tri/splitramp 163 LFO switch to decouple from keytracking. 164 165Mixer: 166 167 Gain levels for Oscillator 1/2/3 168 Mixing of the external input source into filter 169 Noise source with white/pink switch. 170 171 Note: The level at which Osc-3 and noise modulates sound depends on its 172 gain here, similarly the noise. The modulator mix also affects this, but 173 allows Osc-3 to mod as well as sound. The modwheel also affect depth. 174 175Filter: 176 177 Cutoff frequency 178 179 Emphasis (affects Q and resonance of filter). 180 181 Contour: defines how much the filter envelope affects cutoff. 182 183 Mod - Keyboard tracking of cutoff frequency. 184 185 Mod - Osc-3/noise modulation of cutoff frequency. 186 187Contour: 188 189 The synth had two envelope generators, one for the filter and one for the 190 amplifier. Release is affected by the release switch. If off the the sound 191 will release at the rate of the decay control. 192 193 Attack: initial ramp up of gain. 194 195 Decay: fall off of maximum signal down to: 196 197 Sustain: gain level for constant key-on level. 198 199 Key: Touch sensitivity of amplifier envelope. 200 201Improvements to the Mini would be some better oscillator waveforms, plus an 202alternative filter as this is a relatively simple synthesiser and could do 203with a warmer filter (this was fixed with integration of the houvillanen filters 204although the do consume a lot of CPU to do it). 205 206The Output selection has a Midi channel up/down selector and memory selector. 207To read a memory either use the up/down arrows to go to the next available 208memory, or type in a 3 digit number on the telephone keypad and press 'L' for 209load or 'S' for save. 210 211As of release 0.20.5 Vasiliy Basic contributed his Mini memory banks and they 212are now a part of the distribution: 213 214Programs for Bristol's "Mini" (from 50 to 86 PRG) 215 216List of programs: 217 218 -Melodic- 219 50 - Trumpet 220 51 - Cello 221 52 - Guitar 1 222 53 - Guitar 2 223 54 - Fingered Bass 224 55 - Picked Bass 225 56 - Harmonica 226 57 - Accordion 227 58 - Tango Accordion 228 59 - Super Accordion 229 60 - Piano 230 61 - Dark Organ 231 62 - Flute 232 63 - Music Box 233 64 - Glass Xylo 234 65 - Glass Pad 235 66 - Acid Bass 236 237 -Drums- 238 67 - Bass Drum 1 239 68 - Bass Drum 2 240 69 - Bass Drum 3 241 70 - Bass Drum 4 242 71 - Tom 243 72 - Snare 1 244 73 - Snare 2 245 74 - Snare 3 246 75 - Snare 4 247 76 - Cl HH 1 248 77 - Op HH 1 249 78 - Crash Cym 1 250 79 - Crash Cym 2 251 80 - Cl HH 2 252 81 - Op HH 2 253 254 -FX- 255 82 - Sea Shore 256 83 - Helicopter 1 257 84 - Helicopter 2 258 85 - Bird Tweet 259 86 - Birds Tweet 260 261 262 263 264 Sequential Circuits Prophet-5 265 Sequential Circuits Prophet-52 (the '5' with chorus) 266 ---------------------------------------------------- 267 268Sequential circuits released amongst the first truly polyphonic synthesisers 269where a group of voice circuits (5 in this case) were linked to an onboard 270computer that gave the same parameters to each voice and drove the notes to 271each voice from the keyboard. The device had some limited memories to allow 272for real live stage work. The synth was amazingly flexible regaring the 273oscillator options and modulation routing, producing some of the fattest 274sounds around. They also had some of the fattest pricing as well, putting it 275out of reach of all but the select few, something that maintained its mythical 276status. David Sylvian of Duran Duran used the synth to wide acclaim in the 277early 80's as did many of the new wave of bands. 278 279The -52 is the same as the -5 with the addition of a chorus as it was easy, it 280turns the synth stereo for more width to the sound, and others have done it on 281the Win platform. 282 283The design of the Prophet synthesisers follows that of the Mini Moog. It has 284three oscillators one of them as a dedicated LFO. The second audio oscillator 285can also function as a second LFO, and can cross modulate oscillator A for FM 286type effects. The audible oscillators have fixed waveforms with pulse width 287modulation of the square wave. These are then mixed and sent to the filter with 288two envelopes, for the filter and amplifier. 289 290Modulation bussing is quite rich. There is the wheel modulation which is global, 291taking the LFO and Noise as a mixed source, and send it under wheel control to 292any of the oscillator frequency and pulse width, plus the filter cutoff. Poly 293mods take two sources, the filter envelope and Osc-B output (which are fully 294polyphonic, or rather, independent per voice), and can route them through to 295Osc-A frequency and Pulse Width, or through to the filter. To get the filter 296envelope to actually affect the filter it needs to go through the PolyMod 297section. Directing the filter envelope to the PW of Osc-A can make wide, breathy 298scanning effects, and when applied to the frequency can give portamento effects. 299 300LFO: 301 302 Frequency: 0.1 to 50 Hz 303 Shape: Ramp/Triangle/Square. All can be selected, none selected should 304 give a sine wave (*) 305 306 (*) Not yet implemented. 307 308Wheel Mod: 309 310 Mix: LFO/Noise 311 Dest: Osc-A Freq/Osc-B Freq/Osc-A PW/Osc-B PW/Filter Cutoff 312 313Poly Mod: These are affected by key velocity. 314 315 Filter Env: Amount of filter envelope applied 316 Osc-B: Amount of Osc-B applied: 317 Dest: Osc-A Freq/Osc-A PW/Filter Cutoff 318 319Osc-A: 320 321 Freq: 32' to 1' in octave steps 322 Shape: Ramp or Square 323 Pulse Width: only when Square is active. 324 Sync: synchronise to Osc-B 325 326Osc-B: 327 328 Freq: 32' to 1' in octave steps 329 Fine: +/- 7 semitones 330 Shape: Ramp/Triangle/Square 331 Pulse Width: only when Square is active. 332 LFO: Lowers frequency by 'several' octaves. 333 KBD: enable/disable keyboard tracking. 334 335Mixer: 336 337 Gain for Osc-A, Osc-B, Noise 338 339Filter: 340 341 Cutoff: cuttof frequency 342 Res: Resonance/Q/Emphasis 343 Env: amount of PolyMod affecting to cutoff. 344 345Envelopes: One each for PolyMod (filter) and amplifier. 346 347 Attack 348 Decay 349 Sustain 350 Release 351 352Global: 353 354 Master Volume 355 A440 - stable sine wave at A440 Hz for tuning. 356 Midi: channel up/down 357 Release: release all notes 358 Tune: autotune oscillators. 359 Glide: amount of portamento 360 361 Unison: gang all voices to a single 'fat' monophonic synthesiser. 362 363This is one of the fatter of the Bristol synths and the design of the mods 364is impressive (not my design, this is as per sequential circuits spec). Some 365of the cross modulations are noisy, notably 'Osc-B->Freq Osc-A' for square 366waves as dest and worse as source. 367 368The chorus used by the Prophet-52 is a stereo 'Dimension-D' type effect. The 369signal is panned from left to right at one rate, and the phasing and depth at 370a separate rate to generate subtle chorus through to helicopter flanging. 371 372Memories are loaded by selecting the 'Bank' button and typing in a two digit 373bank number followed by load. Once the bank has been selected then 8 memories 374from the bank can be loaded by pressing another memory select and pressing 375load. The display will show free memories (FRE) or programmed (PRG). 376 377 378 379 380 Yamaha DX-7 381 ----------- 382 383Released in the '80s this synth quickly became the most popular of all time. 384It was the first fully digital synth, employed a revolutionary frequency 385modulated algorithm and was priced much lower than the analogue monsters 386that preceded it. Philip Glass used it to wide effect for Miami Vice, Prince 387had it on many of his albums, Howard Jones produced albums filled with its 388library sounds. The whole of the 80's were loaded with this synth, almost to 389the point of saturation. There was generally wide use of its library sounds 390due to the fact that it was nigh on impossible to programme, only having entry 391buttons and the algorithm itself was not exactly intuitive, but also because 392the library was exceptional and the voices very playable. The emulation is a 3936 operator per voice, and all the parameters are directly accessible to ease 394programming. 395 396The original DX had six operators although cheaper models were release with 397just 4 operators and a consequently thinner sound. Each operator is a sine 398wave oscillator with its own envelope generator for amplification and a few 399parameters that adjusted its modulators. It used a number of different 400algorithms where operators were mixed together and then used to adjust the 401frequency of the next set of operators. The sequence of the operators affected 402the net harmonics of the overall sound. Each operator has a seven stage 403envelope - 'ramp' to 'level 1', 'ramp' to 'level 2', 'decay' to 'sustain', 404and finally 'release' when a key is released. The input gain to the frequency 405modulation is controllable, the output gain is also adjustable, and the final 406stage operators can be panned left and right. 407 408Each operator has: 409 410 Envelope: 411 412 Attack: Ramp rate to L1 413 L1: First target gain level 414 Attack: Ramp rate from L2 to L2 415 L2: Second target gain level 416 Decay: Ramp rate to sustain level 417 Sustain: Continuous gain level 418 Release: Key release ramp rate 419 420 Tuning: 421 422 Tune: +/- 7 semitones 423 Transpose: 32' to 1' in octave increments 424 425 LFO: Low frequency oscillation with no keyboard control 426 427 Gain controls: 428 429 Touch: Velocity sensitivity of operator. 430 431 In gain: Amount of frequency modulation from input 432 Out gain: Output signal level 433 434 IGC: Input gain under Mod control 435 OGC: Output gain under Mod control 436 437 Pan: L/R pan of final stage operators. 438 439Global and Algorithms: 440 441 24 different operator staging algorithms 442 Pitchwheel: Depth of pitch modifier 443 Glide: Polyphonic portamento 444 Volume 445 Tune: Autotune all operators 446 447Memories can be selected with either submitting a 3 digit number on the keypad, 448or selecting the orange up/down buttons. 449 450An improvement could be more preset memories with different sounds that can 451then be modified, ie, more library sounds. There are some improvements that 452could be made to polyphonic mods from key velocity and channel/poly pressure 453that would not be difficult to implement. 454 455The addition of triangle of other complex waveforms could be a fun development 456effort (if anyone were to want to do it). 457 458The DX still has a prependancy to seg fault, especially when large gains are 459applied to input signals. This is due to loose bounds checking that will be 460extended in a present release. 461 462 463 464 465 Roland Juno-60 466 -------------- 467 468Roland was one of the main pacemakers in analogue synthesis, also competing 469with the Sequential and Oberheim products. They did anticipate the moving 470market and produced the Juno-6 relatively early. This was one of the first 471accessible synths, having a reasonably fat analogue sound without the price 472card of the monster predecessors. It brought synthesis to the mass market that 473marked the decline of Sequential Circuits and Oberheim who continued to make 474their products bigger and fatter. The reduced price tag meant it had a slightly 475thinner sound, and a chorus was added to extend this, to be a little more 476comparable. 477 478The synth again follows the Mini Moog design of oscillators into filter into 479amp. The single oscillator is fattened out with harmonics and pulse width 480modulation. There is only one envelope generator that can apply to both the 481filter and amplifier. 482 483Control: 484 485 DCO: Amount of pitch wheel that is applied to the oscillators frequency. 486 VCF: Amount of pitch wheel that is applied to the filter frequency. 487 488 Tune: Master tuning of instrument 489 490 Glide: length of portamento 491 492 LFO: Manual control for start of LFO operation. 493 494Hold: (*) 495 496 Transpose: Up/Down one octave 497 Hold: prevent key off events 498 499LFO: 500 501 Rate: Frequency of LFO 502 Delay: Period before LFO is activated 503 Man/Auto: Manual or Automatic cut in of LFO 504 505DCO: 506 507 LFO: Amount of LFO affecting frequency. Affected by mod wheel. 508 PWM: Amount of LFO affecting PWM. Affected by mod wheel. 509 510 ENV/LFO/MANUAL: Modulator for PWM 511 512 Waveform: 513 Pulse or Ramp wave. Pulse has PWM capabily. 514 515 Sub oscillator: 516 On/Off first fundamental square wave. 517 518 Sub: 519 Mixer for fundamental 520 521 Noise: 522 Mixer of white noise source. 523 524HPF: High Pass Filter 525 526 Freq: 527 Frequency of cutoff. 528 529VCF: 530 531 Freq: 532 Cutoff frequency 533 534 Res: 535 Resonance/emphasis. 536 537 Envelope: 538 +ve/-ve application 539 540 Env: 541 Amount of contour applied to cutoff 542 543 LFO: 544 Depth of LFO modulation applied. 545 546 KBD: 547 Amount of key tracking applied. 548 549VCA: 550 551 Env/Gate: 552 Contour is either gated or modulated by ADSR 553 554 Level: 555 Overall volume 556 557ADSR: 558 559 Attack 560 Decay 561 Sustain 562 Release 563 564Chorus: 565 566 8 Selectable levels of Dimension-D type helicopter flanger. 567 568* The original instrument had a basic sequencer on board for arpeggio effects 569on each key. In fact, so did the Prophet-10 and Oberheims. This was only 570implemented in 0.10.11. 571 572The LFO cut in and gain is adjusted by a timer and envelope that it triggers. 573 574The Juno would improve from the use of the prophet DCO rather than its own one. 575It would require a second oscillator for the sub frequency, but the prophet DCO 576can do all the Juno does with better resampling and PWM generation. 577 578 579 580 581 Moog Voyager (Bristol "Explorer") 582 --------------------------------- 583 584This was Robert Moog's last synth, similar in build to the Mini but created 585over a quarter of a century later and having far, far more flexibility. It 586was still monophonic, a flashback to a legendary synth but also a bit like 587Bjorn Borg taking his wooden tennis racket back to Wimbledon long after having 588retired and carbon fibre having come to pass. I have no idea who uses it and 589Bjorn also crashed out in the first round. The modulation routing is exceptional 590if not exactly clear. 591 592The Voyager, or Bristol Explorer, is definitely a child of the Mini. It has 593the same fold up control panel, three and half octave keyboard and very much 594that same look and feel. It follows the same rough design of three oscillators 595mixed with noise into a filter with envelopes for the filter and amplifier. 596In contrast there is an extra 4th oscillator, a dedicated LFO bus also Osc-3 597can still function as a second LFO here. The waveforms are continuously 598selected, changing gradually to each form: bristol uses a form of morphing 599get get similar results. The envelopes are 4 stage rather than the 3 stage 600Mini, and the effects routing bears no comparison at all, being far more 601flexible here. 602 603Just because its funny to know, Robert Moog once stated that the most difficult 604part of building and releasing the Voyager was giving it the title 'Moog'. He 605had sold his company in the seventies and had to buy back the right to use his 606own name to release this synthesiser as a Moog, knowing that without that title 607it probably would not sell quite as well as it didn't. 608 609Control: 610 611 LFO: 612 Frequency 613 Sync: LFO restarted with each keypress. 614 615 Fine tune +/- one note 616 Glide 0 to 30 seconds. 617 618Modulation Busses: 619 620 Two busses are implemented. Both have similar capabilities but one is 621 controlled by the mod wheel and the other is constantly on. Each bus has 622 a selection of sources, shaping, destination selection and amount. 623 624 Wheel Modulation: Depth is controller by mod wheel. 625 626 Source: Triwave/Ramp/Sample&Hold/Osc-3/External 627 Shape: Off/Key control/Envelope/On 628 Dest: All Osc Frequency/Osc-2/Osc-3/Filter/FilterSpace/Waveform (*) 629 Amount: 0 to 1. 630 631 Constant Modulation: Can use Osc-3 as second LFO to fatten sound. 632 633 Source: Triwave/Ramp/Sample&Hold/Osc-3/External 634 Shape: Off/Key control/Envelope/On 635 Dest: All Osc Frequency/Osc-2/Osc-3/Filter/FilterSpace/Waveform (*) 636 Amount: 0 to 1. 637 638 * Destination of filter is the cutoff frequency. Filter space is the 639 difference in cutoff of the two layered filters. Waveform destination 640 affects the continuously variable oscillator waveforms and allows for 641 Pulse Width Modulation type effects with considerably more power since 642 it can affect ramp to triangle for example, not just pulse width. 643 644Oscillators: 645 646 Oscillator 1: 647 Octave: 32' to 1' in octave steps 648 Waveform: Continuous between Triangle/Ramp/Square/Pulse 649 650 Oscillator 2: 651 Tune: Continuous up/down 7 semitones. 652 Octave: 32' to 1' in octave steps 653 Waveform: Continuous between Triangle/Ramp/Square/Pulse 654 655 Oscillator 3: 656 Tune: Continuous up/down 7 semitones. 657 Octave: 32' to 1' in octave steps 658 Waveform: Continuous between Triangle/Ramp/Square/Pulse 659 660 Sync: Synchronise Osc-2 to Osc-1 661 FM: Osc-3 frequency modulates Osc-1 662 KBD: Keyboard tracking Osc-3 663 Freq: Osc-3 as second LFO 664 665Mixer: 666 667 Gain levels for each source: Osc-1/2/3, noise and external input. 668 669Filters: 670 671 There are two filters with different configuration modes: 672 673 1. Two parallel resonant lowpass filters. 674 2. Serialised HPF and resonant LPF 675 676 Cutoff: Frequency of cutoff 677 Space: Distance between the cutoff of the two filters. 678 Resonance: emphasis/Q. 679 KBD tracking amount 680 Mode: Select between the two operating modes. 681 682Envelopes: 683 684 Attack 685 Decay 686 Sustain 687 Release 688 689 Amount to filter (positive and negative control) 690 691 Velocity sensitivity of amplifier envelope. 692 693Master: 694 695 Volume 696 LFO: Single LFO or one per voice (polyphonic operation). 697 Glide: On/Off portamento 698 Release: On/Off envelope release. 699 700The Explorer has a control wheel and a control pad. The central section has 701the memory section plus a panel that can modify any of the synth parameters as 702a real time control. Press the first mouse key here and move the mouse around 703to adjust the controls. Default values are LFO frequency and filter cutoff 704but values can be changed with the 'panel' button. This is done by selecting 705'panel' rather than 'midi', and then using the up/down keys to select parameter 706that will be affected by the x and y motion of the mouse. At the moment the 707mod routing from the pad controller is not saved to the memories, and it will 708remain so since the pad controller is not exactly omnipresent on MIDI master 709keyboards - the capabilities was put into the GIU to be 'exact' to the design. 710 711This synth is amazingly flexible and difficult to advise on its best use. Try 712starting by mixing just oscillator 1 through to the filter, working on mod 713and filter options to enrich the sound, playing with the oscillator switches 714for different effects and then slowly mix in oscillator 2 and 3 as desired. 715 716Memories are available via two grey up/down selector buttons, or a three digit 717number can be entered. There are two rows of black buttons where the top row 718is 0 to 4 and the second is 5 to 9. When a memory is selected the LCD display 719will show whether it is is free (FRE) or programmed already (PRG). 720 721 722 723 724 Hammond B3 (dual manual) 725 ------------------------ 726 727The author first implemented the Hammond module, then extended it to the B3 728emulation. Users of this are too numerous to mention and the organ is still 729popular. Jimmy Smith, Screaming Jay Hawkins, Kieth Emerson, Doors and 730almost all american gospel blues. Smith was profuse, using the instrument for 731a jazz audience, even using its defects (key noise) to great effect. Emerson 732had two on stage, one to play and another to kick around, even including 733stabbing the keyboard with a knife to force keylock during performances 734(Emerson was also a Moog fan with some of the first live performances). He 735also used the defects of the system to great effect, giving life to the over- 736driven Hammond sound. 737 738The Hammond was historically a mechanical instrument although later cheaper 739models used electronics. The unit had a master motor that rotated at 740the speed of the mains supply. It drove a spindle of cog wheels and next to 741each cog was a pickup. The pickup output went into the matrix of the harmonic 742drawbars. It was originally devised to replace the massive pipe organs in 743churches - Hammond marketed their instruments with claims that they could not be 744differentiated from the mechanical pipe equivalent. He was taken to court by 745the US government for misrepresentation, finally winning his case using a double 746blind competitive test against a pipe organ, in a cathedral, with speakers 747mounted behind the organ pipes and an array of music scholars, students and 748professionals listening. The results spoke for themselves - students would 749have scored better by simply guessing which was which, the professionals 750fared only a little better than that. The age of the Hammond organ had arrived. 751 752The company had a love/hate relationship with the Leslie speaker company - the 753latter making money by selling their rotary speakers along with the organ to 754wide acceptance. The fat hammond 'chorus' was a failed attempt to distance 755themselves from Leslie. That was never achieved due to the acceptance of the 756Leslie, but the chorus did add another unique sound to the already awesome 757instrument. The rotary speaker itself still added an extra something to the 758unique sound that is difficult imagine one without the other. It has a wide 759range of operating modes most of which are included in this emulator. 760 761The chorus emulation is an 8 stage phase shifting filter algorithm with a 762linear rotor between the taps. 763 764Parameterisation of the first B3 window follows the original design: 765 766 Leslie: Rotary speaker on/off 767 Reverb: Reverb on/off 768 VibraChorus: 3 levels of vibrato, 3 of chorus. 769 Bright: Added upper harmonics to waveforms. 770 771Lower and Upper Manual Drawbars: The drawbars are colour coded into white for 772even harmonics and black for odd harmonics. There are two subfrequencies in 773brown. The number given here are the length of organ pipe that would 774correspond to the given desired frequency. 775 776 16 - Lower fundamental 777 5 1/3 - Lower 3rd fundamental 778 8 - Fundamental 779 4 - First even harmonic 780 2 2/3 - First odd harmonic 781 2 - Second even harmonic 782 1 3/5 - Second odd harmonic 783 1 1/3 - Third odd harmonic 784 1 - Third even harmonic 785 786The drawbars are effectively mixed for each note played. The method by which 787the mixing is done is controlled in the options section below. There were 788numerous anomalies shown by the instrument and most of them are emulated. 789 790The Hammond could provide percussives effect the first even and odd harmonics. 791This gave a piano like effect and is emulated with Attack/Decay envelope. 792 793 Perc 4' - Apply percussive to the first even harmonic 794 Perc 2 2/3' - Apply percussive to the first odd harmonic 795 Slow - Adjust rate of decay from about 1/2 second to 4 seconds. 796 797 Soft - Provide a soft attack to each note. 798 799The soft attack is an attempt to reduce the level of undesired key noise. The 800keyboard consisted of a metal bar under each key that made physical contact 801with 9 sprung teeth to tap off the harmonics. The initial contact would generate 802noise that did not really accord to the pipe organ comparison. This was 803reduced by adding a slow start to each key, but the jazz musicians had used 804this defect to great effect, terming it 'key click' and it became a part of 805the Hammond characteristics. Some musicians would even brag about how noisy 806there organ was. 807 808On the left had side are three more controls: 809 810 Volume potentiometer 811 812 Options switch discussed below. 813 814 Rotary Speed: low/high speed Leslie rotation. Shifts between the speeds 815 are suppressed to emulate the spin up and down periods of the leslie motors. 816 817The options section, under control of the options button, has the parameters 818used to control the emulation. These are broken into sections and discussed 819individually. 820 821Leslie: 822 823The Leslie rotary speaker consisted of a large cabinet with a bass speaker and 824a pair of high frequency air horns. Each were mounted on its own rotating table 825and driven around inside the cabinet by motors. A crossover filter was used to 826separate the frequencies driven to either speaker. Each pair was typically 827isolated physically from the other. As the speaker rotated it would generate 828chorus type effects, but far richer in quality. Depending on where the speaker 829was with respect to the listener the sound would also appear to rotate. There 830would be different phasing effects based on signal reflections, different 831filtering effects depending on where the speaker was in respect to the cabinet 832producing differences resonances with respect to the internal baffling. 833 834 Separate: 835 Sync: 836 No Bass: 837 The Leslie had two motors, one for the horns and one for the voice coil 838 speaker. These rotated at different speeds. Some players preferred to 839 have both rotate at the same speed, would remove the second motor and 840 bind the spindles of each speaker table, this had the added effect 841 that both would also spin up at the same rate, not true of the 842 separated motors since each table had a very different rotary moment. 843 The 'No Bass' option does not rotate the voice coil speaker. This was 844 typically done since it would respond only slowly to speed changes, 845 this left just the horns rotating but able to spin up and down faster. 846 847 Brake: 848 Some cabinets had a brake applied to the tables such that when the 849 motor stopped the speakers slowed down faster. 850 851 X-Over: 852 This is the cross over frequency between the voice coil and air horns. 853 Uses a butterworth filter design. 854 855 Inertia: 856 Rate at which speaker rotational speed will respond to changes. 857 858 Overdrive: 859 Amount by which the amplifier is overdriven into distortion. 860 861 H-Depth/Frequency/Phase 862 L-Depth/Frequency/Phase 863 These parameters control the rotary phasing effect. The algorithm used 864 has three differently phased rotations used for filtering, phasing and 865 reverberation of the sound. These parameters are used to control the 866 depth and general phasing of each of them, giving different parameters 867 for the high and low speed rotations. There are no separate parameters 868 for the voice coil or air horns, these parameters are for the two 869 different speeds only, although in 'Separate' mode the two motors will 870 rotate at slightly different speeds. 871 872Chorus 873 874 V1/C1 - Lowest chorus speed 875 V2/C2 - Medium chorus speed 876 V3/C3 - High chorus speed 877 878Percussion: 879 880 Decay Fast/Slow - controls the percussive delay rates. 881 Attack Slow Fast - Controls the per note envelope attack time. 882 883The percussives are emulated as per the original design where there was a 884single envelope for the whole keyboard and not per note. The envelope will only 885restrike for a cleanly pressed note. 886 887Finally there are several parameters affecting the sine wave generation code. 888The Hammond used cogged wheels and coil pickups to generate all the harmonics, 889but the output was not a pure sine wave. This section primarily adjusts the 890waveform generation: 891 892 Preacher: 893 The emulator has two modes of operation, one is to generate the 894 harmonics only for each keyed note and another to generate all of 895 them and tap of those required for whatever keys have been pressed. 896 Both work and have different net results. Firstly, generating each 897 note independently is far more efficient than generating all 90 odd 898 teeth, as only a few are typically required. This does not have totally 899 linked phases between notes and cannot provide for signal damping (see 900 below). 901 The Preacher algorithm generates all harmonics continuously as per the 902 original instrument. It is a better rendition at the expense of large 903 chunks of CPU activity. This is discussed further below. 904 905 Compress: 906 Time compress the sine wave to produce a slightly sharper leading edge. 907 908 Bright: 909 Add additional high frequency harmonics to the sine. 910 911 Click: 912 Level of key click noise 913 914 Reverb: 915 Amount of reverb added by the Leslie 916 917 Damping: 918 If the same harmonic was reused by different pressed keys then its net 919 volume would not be a complete sum, the output gain would decay as the 920 pickups would become overloaded. This would dampen the signal strength. 921 This is only available with the Preacher algorithm. 922 923The two reverse octaves are presets as per the original, however here they can 924just be used to recall the first 23 memories of the current bank. The lower 925manual 12 key is the 'save' key for the current settings and must be double 926clicked. It should be possible to drive these keys via MIDI, not currently 927tested though. The default presets are a mixture of settings, the lower 928manual being typical 'standard' recital settings, the upper manual being a 929mixture of Smith, Argent, Emerson, Winwood and other settings from the well 930known Hammond Leslie FAQ. You can overwrite them. As a slight anomaly, which 931was intentional, loading a memory from the these keys only adjusts the visible 932parameters - the drawbars, leslie, etc. The unseen ones in the options panel 933do not change. When you save a memory with a double click on the lower manual 934last reverse key then in contrast it saves all the parameters. This will not 935change. 936 937The Preacher algorithm supports a diverse set of options for its tonewheel 938emulation. These are configured in the file $BRISTOL/memory/profiles/tonewheel 939and there is only one copy. The file is a text file and will remain that way, 940it is reasonably documented in the file itself. Most settings have two ranges, 941one representing the normal setting and the other the bright setting for when 942the 'bright' button is pressed. The following settings are currently available: 943 944 ToneNormal: each wheel can be given a waveform setting from 0 (square) 945 through to 1.0 (pure sine) to X (sharpening ramp). 946 947 EQNormal: each wheel can be given a gain level across the whole generator. 948 949 DampNormal: each wheel has a damping factor (level robbing/damping/stealing) 950 951 BusNormal: each drawbar can be equalised globally. 952 953 954 ToneBright: each wheel can be given a waveform setting from 0 (square) 955 through to 1.0 (pure sine) to X (sharpening ramp) for the bright button. 956 957 EQBright: each wheel can be given a gain level across the whole generator. 958 959 DampBright: each wheel has a damping factor (level robbing/damping/stealing) 960 961 BusBright: each drawbar can be equalised globally. 962 963 964 stops: default settings for the eight drawbar gain levels. 965 966 The default is 8 linear stages. 967 968 wheel: enables redefining the frequency and phase of any given tonewheel 969 970 The defaults are the slightly non Even Tempered frequencies of the 971 Hammond tonewheels. The tonewheel file redefines the top 6 frequencies 972 that were slightly more out of tune due to the 192-teeth wheels and 973 a different gear ratio. 974 975 crosstalk: between wheels in a compartment and adjacent drawbar busses. 976 977 This is one area that may need extensions for crosstalk in the wiring 978 loom. Currently the level of crosstalk between each of the wheels in 979 the compartment can be individually defined, and drawbar bus crosstalk 980 also. 981 982 compartment: table of the 24 tonewheel compartments and associated wheels. 983 984 resistors: tapering resister definitions for equalisation of gains per 985 wheel by note by drawbar. 986 987 taper: definition of the drawbar taper damping resistor values. 988 989Improvements would come with some other alterations to the sine waveforms and 990some more EQ put into the leslie speaker. The speaker has three speeds, two of 991which are configurable and the third is 'stopped'. Changes between the different 992rates is controlled to emulate inertia. 993 994The net emulation, at least of the preacher algorithm, is reasonable, it is 995distinctively a Hammond sound although it does not have quite as much motor 996or spindle noise. The Bright button gives a somewhat rawer gearbox. It could do 997with a better amplifier emulation for overdrive. 998 999The damping algorithms is not quite correct, it has dependencies on which keys 1000are pressed (upper/lower manual). Options drop shadow is taken from the wrong 1001background bitmap so appears in an inconsistent grey. 1002 1003 1004 1005 1006 Vox Continental 1007 --------------- 1008 1009This emulates the original mark-1 Continental, popular in its time with the 1010Animals on 'House of the Rising Sun', Doors on 'Light my Fire' and most of 1011their other tracks. Manzarek did use Gibson later, and even played with the 1012Hammond on their final album, 'LA Woman' but this organ in part defined 1013the 60's sound and is still used by retro bands for that fact. The Damned 1014used it in an early revival where Captain Sensible punched the keyboard 1015wearing gloves to quite good effect. After that The Specials began the Mod/Ska 1016revival using one. The sharp and strong harmonic content has the ability to 1017cut into a mix and make its presence known. 1018 1019The organ was a british design, eventually sold (to Crumar?) and made into a 1020number of plastic alternatives. Compared to the Hammond this was a fully 1021electronic instrument, no moving parts, and much simpler. It had a very 1022characteristic sound though, sharper and perhaps thinner but was far cheaper 1023than its larger cousin. It used a master oscillator that was divided down to 1024each harmonic for each key (as did the later Hammonds for price reasons). This 1025oscillator division design was used in the first of the polyphonic synthesisers 1026where the divided note was fead through individual envelope generators and 1027a shared or individual filter (Polymoog et al). 1028 1029The Vox is also a drawbar instrument, but far simplified compared to the 1030Hammond. It has 4 harmonic mixes, 16', 8' and 4' drawbars each with eight 1031positions. The fourth gave a mix of 2 2/3, 2, 1 1/3 and 1 foot pipes. 1032An additional two drawbars controlled the overall volume and waveforms, one 1033for the flute or sine waves and another for the reed or ramp waves. The 1034resulting sound could be soft and warm (flute) or sharp and rich (reed). 1035 1036There are two switches on the modulator panel, one for vibrato effect and one 1037for memories and options. Options give access to an chorus effect rather 1038than the simple vibrato, but this actually detracts from the qualities of the 1039sound which are otherwise very true to the original. 1040 1041Vox is a trade name owned by Korg Inc. of Japan, and Continental is one of 1042their registered trademarks. Bristol does not intend to infringe upon these 1043registered names and Korg have their own remarkable range of vintage emulations 1044available. You are directed to their website for further information of true 1045Korg products. 1046 1047 1048 1049 1050 Fender Rhodes 1051 ------------- 1052 1053Again not an instrument that requires much introduction. This emulation is 1054the DX-7 voiced synth providing a few electric piano effects. The design is 1055a Mark-1 Stage-73 that the author has, and the emulation is reasonable if not 1056exceptional. The Rhodes has always been widely used, Pink Floyd on 'Money', 1057The Doors on 'Riders on the Storm', Carlos Santana on 'She's not There', 1058everybody else in the 60's. 1059 1060The Rhodes piano generated its sound using a full piano action keyboard where 1061each hammer would hit a 'tine', or metal rod. Next to each rod was a pickup 1062coil as found on a guitar, and these would be linked together into the output. 1063The length of each tine defined its frequency and it was tunable using a tight 1064coiled spring that could be moved along the length of the tine to adjust its 1065moment. The first one was built mostly out of aircraft parts to amuse injured 1066pilots during the second world war. The Rhodes company was eventually sold to 1067Fender and lead to several different versions, the Mark-2 probably being the 1068most widely acclaimed for its slightly warmer sound. 1069 1070There is not much to explain regarding functionality. The emulator has a volume 1071and bass control, and one switch that reveals the memory buttons and algorithm 1072selector. 1073 1074The Rhodes would improve with the addition of small amounts of either reverb 1075or chorus, potentially to be implemented in a future release. 1076 1077The Rhodes Bass was cobbled together largely for a presentation on Bristol. 1078It existed and was used be Manzarek when playing with The Doors in 1079Whiskey-a-GoGo; the owner specified that whilst the music was great they 1080needed somebody playing the bass. Rather than audition for the part Manzarek 1081went out and bought a Rhodes Bass and used it for the next couple of years. 1082 1083 1084 1085 1086 Sequential Circuits Prophet-10 1087 ------------------------------ 1088 1089The prophet 10 was the troublesome brother of the Pro-5. It is almost two 1090Prophet-5 in one box, two keyboards and a layering capability. Early models 1091were not big sellers, they were temperamental and liable to be temperature 1092sensitive due to the amount of electronics hidden away inside. The original 1093layering and 'unison' allowed the original to function as two independent 1094synths, a pair of layered synths (both keyboards then played the same sound), 1095as a monophonic synth in 'unison' mode on one keybaord with a second polyphonic 1096unit on the other, or even all 10 voices on a single keyed note for a humongous 109720 oscillator monophonic monster. 1098 1099Phil Collins used this synth, and plenty of others who might not admit to it. 1100 1101The emulator uses the same memories as the Prophet-5, shares the same algorithm, 1102but starts two synths. Each of the two synths can be seen by selecting the U/D 1103(Up/Down) button in the programmer section. Each of the two synthesisers loads 1104one of the Pro-5 memories. 1105 1106There was an added parameter - the Pan or balance of the selected layer, used 1107to build stereo synths. The lower control panel was extended to select the 1108playing modes: 1109 1110 Dual: Two independent keyboards 1111 Poly: Play note from each layer alternatively 1112 Layer: Play each layer simultaneously. 1113 1114In Poly and Layer mode, each keyboard plays the same sounds. 1115 1116 Mods: Select which of the Mod and Freq wheels control which layers. 1117 1118 1119 1120 1121 Sequential Circuits Prophet-5 1122 Sequential Circuits Prophet-52 (the '5' with chorus) 1123 ---------------------------------------------------- 1124 1125Sequential circuits released amongst the first truly polyphonic synthesisers 1126where a group of voice circuits (5 in this case) were linked to an onboard 1127computer that gave the same parameters to each voice and drove the notes to 1128each voice from the keyboard. The device had some limited memories to allow 1129for real live stage work. The synth was amazingly flexible regaring the 1130oscillator options and modulation routing, producing some of the fattest 1131sounds around. They also had some of the fattest pricing as well, putting it 1132out of reach of all but the select few, something that maintained its mythical 1133status. David Sylvian of Duran Duran used the synth to wide acclaim in the 1134early 80's as did many of the new wave of bands. 1135 1136The -52 is the same as the -5 with the addition of a chorus as it was easy, it 1137turns the synth stereo for more width to the sound, and others have done it on 1138the Win platform. 1139 1140The design of the Prophet synthesisers follows that of the Mini Moog. It has 1141three oscillators one of them as a dedicated LFO. The second audio oscillator 1142can also function as a second LFO, and can cross modulate oscillator A for FM 1143type effects. The audible oscillators have fixed waveforms with pulse width 1144modulation of the square wave. These are then mixed and sent to the filter with 1145two envelopes, for the filter and amplifier. 1146 1147Modulation bussing is quite rich. There is the wheel modulation which is global, 1148taking the LFO and Noise as a mixed source, and send it under wheel control to 1149any of the oscillator frequency and pulse width, plus the filter cutoff. Poly 1150mods take two sources, the filter envelope and Osc-B output (which are fully 1151polyphonic, or rather, independent per voice), and can route them through to 1152Osc-A frequency and Pulse Width, or through to the filter. To get the filter 1153envelope to actually affect the filter it needs to go through the PolyMod 1154section. Directing the filter envelope to the PW of Osc-A can make wide, breathy 1155scanning effects, and when applied to the frequency can give portamento effects. 1156 1157LFO: 1158 1159 Frequency: 0.1 to 50 Hz 1160 Shape: Ramp/Triangle/Square. All can be selected, none selected should 1161 give a sine wave (*) 1162 1163 (*) Not yet implemented. 1164 1165Wheel Mod: 1166 1167 Mix: LFO/Noise 1168 Dest: Osc-A Freq/Osc-B Freq/Osc-A PW/Osc-B PW/Filter Cutoff 1169 1170Poly Mod: These are affected by key velocity. 1171 1172 Filter Env: Amount of filter envelope applied 1173 Osc-B: Amount of Osc-B applied: 1174 Dest: Osc-A Freq/Osc-A PW/Filter Cutoff 1175 1176Osc-A: 1177 1178 Freq: 32' to 1' in octave steps 1179 Shape: Ramp or Square 1180 Pulse Width: only when Square is active. 1181 Sync: synchronise to Osc-B 1182 1183Osc-B: 1184 1185 Freq: 32' to 1' in octave steps 1186 Fine: +/- 7 semitones 1187 Shape: Ramp/Triangle/Square 1188 Pulse Width: only when Square is active. 1189 LFO: Lowers frequency by 'several' octaves. 1190 KBD: enable/disable keyboard tracking. 1191 1192Mixer: 1193 1194 Gain for Osc-A, Osc-B, Noise 1195 1196Filter: 1197 1198 Cutoff: cuttof frequency 1199 Res: Resonance/Q/Emphasis 1200 Env: amount of PolyMod affecting to cutoff. 1201 1202Envelopes: One each for PolyMod (filter) and amplifier. 1203 1204 Attack 1205 Decay 1206 Sustain 1207 Release 1208 1209Global: 1210 1211 Master Volume 1212 A440 - stable sine wave at A440 Hz for tuning. 1213 Midi: channel up/down 1214 Release: release all notes 1215 Tune: autotune oscillators. 1216 Glide: amount of portamento 1217 1218 Unison: gang all voices to a single 'fat' monophonic synthesiser. 1219 1220This is one of the fatter of the Bristol synths and the design of the mods 1221is impressive (not my design, this is as per sequential circuits spec). Some 1222of the cross modulations are noisy, notably 'Osc-B->Freq Osc-A' for square 1223waves as dest and worse as source. 1224 1225The chorus used by the Prophet-52 is a stereo 'Dimension-D' type effect. The 1226signal is panned from left to right at one rate, and the phasing and depth at 1227a separate rate to generate subtle chorus through to helicopter flanging. 1228 1229Memories are loaded by selecting the 'Bank' button and typing in a two digit 1230bank number followed by load. Once the bank has been selected then 8 memories 1231from the bank can be loaded by pressing another memory select and pressing 1232load. The display will show free memories (FRE) or programmed (PRG). 1233 1234 1235 1236 1237 Oberheim OB-X 1238 ------------- 1239 1240Oberheim was the biggest competitor of Sequential Circuits, having their OB 1241range neck and neck with each SC Prophet. The sound is as fat, the OB-X 1242similar to the Prophet-5 as the OB-Xa to the Prophet-10. The synths were widely 1243used in rock music in the late seventies and early 80s. Their early polyphonic 1244synthesisers had multiple independent voices linked to the keyboard and were 1245beast to program as each voice was configured independently, something that 1246prevented much live usage. The OB-X configured all of the voices with the same 1247parameters and had non-volatile memories for instant recall. 1248 1249Priced at $6000 upwards, this beast was also sold in limited quantities and 1250as with its competition gained and maintained a massive reputation for rich, 1251fat sounds. Considering that it only had 21 continuous controllers they were 1252used wisely to build its distinctive and flexible sound. 1253 1254The general design again follows that of the Mini Moog, three oscillators with 1255one dedicated as an LFO the other two audible. Here there is no mixer though, 1256the two audible oscillators feed directly into the filter and then the amplifier. 1257 1258The richness of the sound came from the oscillator options and filter, the 1259latter of which is not done justice in the emulator. 1260 1261Manual: 1262 1263 Volume 1264 Auto: autotune the oscillators 1265 Hold: disable note off events 1266 Reset: fast decay to zero for envelopes, disregards release parameter. 1267 Master Tune: up/down one semitone both oscillators. 1268 1269Control: 1270 1271 Glide: up to 30 seconds 1272 Oscillator 2 detune: Up/down one semitone 1273 1274 Unison: gang all voices to a single 'fat' monophonic synthesiser. 1275 1276Modulation: 1277 1278 LFO: rate of oscillation 1279 Waveform: Sine/Square/Sample&Hold of noise src. Triangle if none selected. 1280 1281 Depth: Amount of LFO going to: 1282 Freq Osc-1 1283 Freq Osc-2 1284 Filter Cutoff 1285 1286 PWM: Amount of LFO going to: 1287 PWM Osc-1 1288 PWM Osc-2 1289 1290Oscillators: 1291 1292 Freq1: 32' to 1' in octave increments. 1293 PulseWidth: Width of pulse wave (*). 1294 Freq2: 16' to 1' in semitone increments. 1295 1296 Saw: sawtooth waveform Osc-1 (**) 1297 Puls: Pulse waveform Osc-1 1298 1299 XMod: Osc-1 FW to Osc-2 (***) 1300 Sync: Osc-2 sync to Osc-1 1301 1302 Saw: sawtooth waveform Osc-2 1303 Puls: Pulse waveform Osc-2 1304 1305 * Although this is a single controller it acts independently on each of the 1306 oscillators - the most recent to have its square wave selected will be 1307 affected by this parameter allowing each oscillator to have a different 1308 pulse width as per the original design. 1309 1310 ** If no waveform is selected then a triangle is generated. 1311 1312 *** The original synth had Osc-2 crossmodifying Osc-1, this is not totally 1313 feasible with the sync options as they are not mutually exclusive here. 1314 Cross modulation is noisy if the source or dest wave is pulse, something 1315 that may be fixed in a future release. 1316 1317Filter: 1318 1319 Freq: cutoff frequency 1320 Resonance: emphasis (*) 1321 Mod: Amount of modulation to filter cutoff (**) 1322 1323 Osc-1: Osc-1 to cutoff at full swing. 1324 KDB: Keyboard tracking of cutoff. 1325 1326 Half/Full: Oscillator 2 to Cutoff at defined levels (***) 1327 Half/Full: Noise to Cutoff at defined levels (***) 1328 1329 * In contrast to the original, this filter can self oscillate. 1330 1331 ** The original had this parameter for the envelope level only, not the 1332 other modifiers. Due to the filter implementation here it affects total 1333 depth of the sum of the mods. 1334 1335 *** These are not mutually exclusive. The 'Half' button gives about 1/4, 1336 the 'Full' button full, and both on gives 1/2. They could be made mutually 1337 exclusive, but the same effect can be generated with a little more flexibility 1338 here. 1339 1340Envelopes: One each for filter and amplifier. 1341 1342 Attack 1343 Decay 1344 Sustain 1345 Release 1346 1347The oscillators appear rather restricted at first sight, but the parametrics 1348allow for a very rich and cutting sound. 1349 1350Improvements would be a fatter filter, but this can be argued of all the 1351Bristol synthesisers as they all share the same design. It will be altered in 1352a future release. 1353 1354The OB-X has its own mod panel (most of the rest share the same frequency and 1355mod controls). Narrow affects the depth of the two controllers, Osc-2 will 1356make frequency only affect Osc-2 rather than both leading to beating, or phasing 1357effects if the oscillators are in sync. Transpose will raise the keyboard by 1358one octave. 1359 1360Memories are quite simple, the first group of 8 buttons is a bank, the second 1361is for 8 memories in that bank. This is rather restricted for a digital synth 1362but is reasonably true to the original. If you want more than 64 memories let 1363me know. 1364 1365 1366 1367 1368 Oberheim OB-Xa 1369 -------------- 1370 1371This is almost two OB-X in a single unit. With one keyboard they could provide 1372the same sounds but with added voicing for split/layers/poly options. The OB-Xa 1373did at least work with all 10 voices, had a single keyboard, and is renound for 1374the sounds of van Halen 'Jump' and Stranglers 'Strange Little Girl'. The sound 1375had the capability to cut through a mix to upstage even guitar solo's. Oberheim 1376went on to make the most over the top analogue synths before the cut price 1377alternatives and the age of the DX overcame them. 1378 1379Parameters are much the same as the OB-X as the algorithm shares the same code, 1380with a few changes to the mod routing. The main changes will be in the use of 1381Poly/Split/Layer controllers for splitting the keyboard and layering the sounds 1382of the two integrated synthesisers and the choice of filter algorithm. 1383 1384The voice controls apply to the layer being viewed, selected from the D/U 1385button. 1386 1387Manual: 1388 1389 Volume 1390 Balance 1391 Auto: autotune the oscillators 1392 Hold: disable note off 1393 Reset: fast decay to zero for envelopes, disregards release parameter. 1394 Master Tune: up/down one semitone both oscillators. 1395 1396Control: 1397 1398 Glide: up to 30 seconds 1399 Oscillator 2 detune: Up/down one semitone 1400 1401 Unison: gang all voices to a single 'fat' monophonic synthesiser. 1402 1403Modulation: 1404 1405 LFO: rate of oscillation 1406 Waveform: Sine/Square/Sample&Hold of noise src. Triangle if none selected. 1407 1408 Depth: Amount of LFO going to: 1409 Freq Osc-1 1410 Freq Osc-2 1411 Filter Cutoff 1412 1413 PWM: Amount of LFO going to: 1414 PWM Osc-1 1415 PWM Osc-2 1416 Tremelo 1417 1418Oscillators: 1419 1420 Freq1: 32' to 1' in octave increments. 1421 PulseWidth: Width of pulse wave (*). 1422 Freq2: 16' to 1' in semitone increments. 1423 1424 Saw: sawtooth waveform Osc-1 (**) 1425 Puls: Pulse waveform Osc-1 1426 1427 Env: Application of Filter env to frequency 1428 Sync: Osc-2 sync to Osc-1 1429 1430 Saw: sawtooth waveform Osc-2 1431 Puls: Pulse waveform Osc-2 1432 1433 * Although this is a single controller it acts independently on each of the 1434 oscillators - the most recent to have its square wave selected will be 1435 affected by this parameter allowing each oscillator to have a different 1436 pulse width, as per the original design. 1437 1438 ** If no waveform is selected then a triangle is generated. 1439 1440Filter: 1441 1442 Freq: cutoff frequency 1443 Resonance: emphasis (*) 1444 Mod: Amount of modulation to filter cutoff (**) 1445 1446 Osc-1: Osc-1 to cutoff at full swing. 1447 KDB: Keyboard tracking of cutoff. 1448 1449 Half/Full: Oscillator 2 to Cutoff at defined levels (***) 1450 1451 Noise: to Cutoff at defined levels 1452 4 Pole: Select 2 pole or 4 pole filter 1453 1454 * In contrast to the original, this filter will self oscillate. 1455 1456 ** The original had this parameter for the envelope level only, not the 1457 other modifiers. Due to the filter implementation here it affects total 1458 depth of the sum of the mods. 1459 1460 *** These are not mutually exclusive. The 'Half' button gives about 1/4, 1461 the 'Full' button full, and both on gives 1/2. They could be made mutually 1462 exclusive, but the same effect can be generated with a little more flexibility 1463 here. 1464 1465Envelopes: One each for filter and amplifier. 1466 1467 Attack 1468 Decay 1469 Sustain 1470 Release 1471 1472Mode selection: 1473 1474 Poly: play one key from each layer alternatively for 10 voices 1475 Split: Split the keyboard. The next keypress specifies split point 1476 Layer: Layer each voice on top each other. 1477 1478 D/U: Select upper and lower layers for editing. 1479 1480Modifier Panel: 1481 1482 Rate: Second LFO frequency or Arpeggiator rate (*) 1483 Depth: Second LFO gain 1484 Low: Modifiers will affect the lower layer 1485 Up: Modifiers will affect the upper layer 1486 Multi: Each voice will implement its own LFO 1487 Copy: Copy lower layer to upper layer 1488 1489 Mod 01: Modify Osc-1 in given layer 1490 Mod 02: Modify Osc-2 in given layer 1491 PW: Modify Pulse Width 1492 AMT: Amount (ie, depth) of mods and freq wheels 1493 1494 Transpose: Up or Down one octave. 1495 1496The Arpeggiator code integrated into release 0.20.4 has three main parts, the 1497arpeggiator itself, the arpeggiating sequencer and the chording. All are 1498configured from the left of the main panel. 1499 1500The arpeggiator is governed by the rate control that governs how the code 1501steps through the available keys, an octave selector for 1, 2 or 3 octaves 1502of arpeggiation, and finally the Up/Down/Up+Down keys - the last ones start 1503the arpeggiator. Arpeggiation will only affect the lower layer. 1504 1505When it has been started you press keys on the keyboard (master controller 1506or GUI) and the code will step through each note and octaves of each note 1507in the order they were pressed and according to the direction buttons. The 1508key settings are currently reset when you change the direction and you will 1509have to press the notes again. 1510 1511The sequencer is a modification of the code. Select the Seq button and then 1512a direction. The GUI will program the engine with a series of notes (that can 1513be redefined) and the GUI will sequence them, also only into the lower layer. 1514The sequence will only start when you press a key on the keyboard, this is 1515the starting point for the sequence. You can press multiple notes to have 1516them sequence in unison. Once started you can tweak parameters to control 1517the sound and memory 88 when loaded has the filter envelope closed down, a 1518bit of glide and some heavy mods to give you a starting point for some serious 1519fun. 1520 1521To reprogram the sequence steps you should stop the sequencer, press the PRG 1522button, then the Sequence button: enter the notes you want to use one by one 1523on the keyboard. When finished press the sequence button again, it goes out. 1524Now enable it again - select Seq and a direction and press a note. Press two 1525notes. 1526 1527When you save the memory the OBXa will also save the sequence however there 1528is only one sequence memory - that can be changed if you want to have a sequence 1529memory per voice memory (implemented in 0.20.4). 1530 1531The chord memory is similar to the Unison mode except that Unison plays all 1532voices with the same note. Chording will assign one voice to each notes in 1533the chord for a richer sound. To enable Chording press the 'Hold' button. This 1534is not the same as the original since it used the hold button as a sustain 1535option however that does not function well with a Gui and so it was reused. 1536 1537To reprogram the Chord memory do the following: press the PRG button then the 1538Hold button. You can then press the keys, up to 8, that you want in the chord, 1539and finally hit the Hold button again. The default chord is just two notes, 1540the one you press plus its octave higher. This results in multiple voices 1541per keypress (a total of 3 in Layered mode) and with suitable detune will 1542give a very rich sound. 1543 1544There is only one arpeggiator saved for all the memories, not one per memory 1545as with some of the other implementations. Mail me if you want that changed. 1546 1547 1548 1549The oscillators appear rather restricted at first sight, but the parametrics 1550allow for a very rich and cutting sound. 1551 1552The Copy function on the Mod Panel is to make Poly programming easier - generate the desired sound and then copy the complete parameter set for poly operation. 1553It can also be used more subtly, as the copy operation does not affect balance 1554or detune, so sounds can be copied and immediately panned slightly out of tune to generate natural width in a patch. This is not per the original instrument 1555that had an arpeggiator on the mod panel. 1556 1557The Arpeggiator was first integrated into the OBXa in release 0.20.4 but not 1558widely tested. 1559 1560 1561 1562 1563 KORG MONOPOLY 1564 ------------- 1565 1566A synth suite would not be complete without some example of a Korg instrument, 1567the company was also pivotal in the early synthesiser developments. This is 1568an implementation of their early attempts at polyphonic synthesis, it was 1569either this one or the Poly-6 (which may be implemented later). Other choices 1570would have been the MS series, MS-20, but there are other synth packages that 1571do a better job of emulating the patching flexibility of that synth - Bristol 1572is more for fixed configurations. 1573 1574As with many of the Korg synths (the 800 worked similarly) this is not really 1575true polyphony, and it is the quirks that make it interesting. The synth had 1576four audio oscillators, each independently configurable but which are bussed 1577into a common filter and envelope pair - these are not per voice but rather 1578per instrument. The unit had different operating modes such that the four 1579oscillators can be driven together for a phat synth, independently for a form 1580of polyphony where each is allocated to a different keypress, and a shared 1581mode where they are assigned in groups depending on the number of keys pressed. 1582For example, if only 2 notes are held then each key is sounded on two different 1583oscillators, one key is sounded on all 4 oscillators, and 3 or more have one 1584each. In addition there are two LFOs for modulation and a basic effects option 1585for beefing up the sounds. To be honest to the original synth, this emulation 1586will only request 1 voice from the engine. Korg is one of the few original 1587manufacturers to have survived the transition to digital synthesis and are 1588still popular. 1589 1590One thing that is immediately visible with this synth is that there are a lot 1591of controllers since each oscillator is configured independently. This is in 1592contrast to the true polyphonic synths where one set of controls are given to 1593configure all the oscillators/filters/envelopes. The synth stages do follow the 1594typical synth design, there are modulation controllers and an FX section 1595feeding into the oscillators and filter. The effects section is a set of 1596controllers that can be configured and then enabled/disabled with a button 1597press. The overall layout is rather kludgy, with some controllers that are 1598typically grouped being dispersed over the control panel. 1599 1600Control: 1601 1602 Volume 1603 1604 Arpeg: 1605 Whether arpegiator steps up, down, or down then up. This works in 1606 conjunction with the 'Hold' mode described later. 1607 1608 Glide: glissando note to note. Does not operate in all modes 1609 1610 Octave: Up/Normal/Down one octave transpose of keyboard 1611 1612 Tune: Global tuning of all oscillators +/- 50 cents (*) 1613 Detune: Overall detuning of all oscillators +/- 50 cents (*) 1614 1615 * There is an abundance of 'Tune' controllers. Global Tuning affects all 1616 the oscillators together, then oscillators 2, 3 and 4 have an independent 1617 tune controller, and finally there is 'Detune'. The target was to tune all 1618 the oscillators to Osc-1 using the independent Tune for each, and then use 1619 the global Tune here to have the synth tuned to other instruments. The 1620 Detune control can then be applied to introduce some beating between the 1621 oscillators to fatten the sound without necessarily losing overall tune of 1622 the instrument. 1623 1624Modulation wheels: 1625 1626 Bend: 1627 Intensity: Depth of modulation 1628 Destination: 1629 VCF - Filter cutoff 1630 Pitch - Frequency of all oscillators 1631 VCO - Frequency of selected oscillators (FX selection below). 1632 1633 MG1: Mod Group 1 (LFO) 1634 Intensity: Depth of modulation 1635 Destination: 1636 VCF - Filter cutoff 1637 Pitch - Frequency of all oscillators 1638 VCO - Frequency of selected oscillators (FX selection below). 1639 1640LFO: 1641 1642 MG-1: 1643 Frequency 1644 Waveform - Tri, +ve ramp, -ve ramp, square. 1645 1646 MG-2: 1647 Frequency (Triangle wave only). 1648 1649Pulse Width Control: 1650 1651 Pulse Width Modulation: 1652 Source - Env/MG-1/MG-2 1653 Depth 1654 1655 Pule Width 1656 Width control 1657 1658 These controllers affect Osc-1 though 4 with they are selected for either 1659 square of pulse waveforms. 1660 1661Mode: 1662 1663 The Mono/Poly had 3 operating modes, plus a 'Hold' option that affects 1664 each mode: 1665 1666 Mono: All oscillators sound same key in unison 1667 Poly: Each oscillator is assigned independent key - 4 note poly. 1668 Share: Dynamic assignment: 1669 1 key - 4 oscillators = Mono mode 1670 2 key - 2 oscillators per key 1671 3/4 - 1 oscillator per key = Poly mode 1672 1673 The Hold function operates in 3 different modes: 1674 1675 Mono: First 4 keypresses are memorised, further notes are then chorded 1676 together monophonically. 1677 Poly: 1678 Notes are argeggiated in sequence, new note presses are appended 1679 to the chain. Arpeggiation is up, down or up/down. 1680 Share: 1681 First 4 notes are memorised and are then argeggiated in sequence, 1682 new note presses will transpose the arpeggiation. Stepping is up, 1683 down or up/down. 1684 1685 There are several controllers that affect arpeggation: 1686 1687 Arpeg - direction of stepping 1688 MG-2 - Frequency of steps from about 10 seconds down to 50 bps. 1689 Trigger - Multiple will trigger envelopes on each step. 1690 1691Effects: 1692 1693 There are three main effects, or perhaps rather modulations, that are 1694 controlled in this section. These are vibrato, crossmodulated frequency 1695 and oscillator synchronisation. The application of each mod is configured 1696 with the controllers and then all of them can be enabled/disabled with 1697 the 'Effects' button. This allows for big differences in sound to be 1698 applied quickly and simply as a typical effect would be. Since these mods 1699 apply between oscillators it was envisaged they would be applied in Mono 1700 mode to further fatten the sound, and the Mono mode is actually enabled when 1701 the Effects key is selected (as per the original instrument). The Mode can 1702 be changed afterwards for Effects/Poly for example, and they work with the 1703 arpeggiation function. 1704 1705 X-Mod: frequency crossmodulation between oscillators 1706 Freq: frequency modulation by MG-1 (vibrato) or Envlope (sweep) 1707 1708 Mode: 1709 Syn: Oscillators are synchronised 1710 X-M: Oscillators are crossmodulated 1711 S-X: Oscillators are crossmodulated and synchronised 1712 1713 SNG: 1714 Single mode: synth had a master oscillator (1) and three slaves (2/3/4) 1715 DBL: 1716 Double mode: synth had two master (1/3) and two slaves (2/4) 1717 1718 The overall FX routing depends on the SNG/DBL mode and the selection of 1719 Effects enabled or not according to the table below. This table affects 1720 the FX routing and the modulation wheels discussed in the LFO section above: 1721 1722 -------------------------------------------------- 1723 | FX OFF | FX ON | 1724 | |---------------------------------- 1725 | | Single | Double | 1726 ---------------+--------------+-----------------+---------------| 1727 | VCO-1/Slave | VCO-1 | VCO 2/3/4 | VCO 2/4 | 1728 | | | | | 1729 | Pitch | VCO 1-4 | VCO 1-4 | VCO 1-4 | 1730 | | | | | 1731 | VCF | VCF | VCF | VCF | 1732 ----------------------------------------------------------------- 1733 1734 So, glad that is clear. Application of the modulation wheels to Pitch and 1735 VCF is invariable when they are selected. In contrast, VCO/Slave will have 1736 different destinations depending on the Effects, ie, when effects are on 1737 the modwheels will affect different 'slave' oscillators. 1738 1739 1740Oscillators: 1741 1742 Each oscillator had the following controllers: 1743 1744 Tune (*) 1745 Waveform: Triangle, ramp, pulse, square (**) 1746 Octave: Transpose 16' to 2' 1747 Level: output gain/mix of oscillators. 1748 1749 * Osc-1 tuning is global 1750 ** width of pulse and square wave is governed by PW controller. The 1751 modulation of the pulse waveform is then also controlled by PWM. 1752 1753Noise: 1754 1755 Level: white noise output gain, mixed with oscillators into filter. 1756 1757VCF: 1758 1759 Freq: 1760 Cutoff frequency 1761 1762 Res: 1763 Resonance/emphasis. 1764 1765 Env: 1766 Amount of contour applied to cutoff 1767 1768 KBD: 1769 Amount of key tracking applied. 1770 1771ADSR: Two: filter/PWM/FX, amplifier 1772 1773 Attack 1774 Decay 1775 Sustain 1776 Release 1777 1778 Trigger: 1779 Single: Trigger once until last key release 1780 Multi: Trigger for each key or arpeggiator step. 1781 1782 Damp: 1783 Off: Notes are held in Poly/Share mode until last key is released. 1784 On: Oscillators are released as keys are released. 1785 1786This is more a synth to play with than describe. It never managed to be a true 1787blue synth perhaps largely due to its unusual design: the quasi-poly mode was 1788never widely accepted, and the effects routing is very strange. This does make 1789it a synth to be tweaked though. 1790 1791Some of the mod routings do not conform to the original specification for the 1792different Slave modes. This is the first and probably the only bristol synth that 1793will have an inbuilt arpeggiator. The feature was possible here due to the mono 1794synth specification, and whilst it could be built into the MIDI library for 1795general use it is left up to the MIDI sequencers (that largely came along to 1796replace the 1980s arpeggiators anyway) that are generally availlable on Linux. 1797[Other instruments emulated by bristol that also included arpeggiation but do 1798not have in the emulation were the Juno-6, Prophet-10, Oberheim OB-Xa, Poly6]. 1799 1800As of May 06 this synth was in its final stages of development. There are a few 1801issues with Tune and Detune that need to be fixed, and some of the poly key 1802assignment may be wrong. 1803 1804 1805 1806 1807 KORG POLY 6 1808 ----------- 1809 1810Korg in no way endorses this emulation of their classic synthesiser and have 1811their own emulation product that gives the features offered here. Korg, 1812Mono/Poly, Poly-6, MS-20, Vox and Continental are all registered names or 1813trademarks of Korg Inc of Japan. 1814 1815Quite a few liberties were taken with this synth. There were extremely few 1816differences between the original and the Roland Juno 6, they both had one osc 1817with PWM and a suboscillator, one filter and envelope, a chorus effect, and 1818inevitably both competed for the same market space for their given price. To 1819differentiate this algorithm some alterations were made. There are two separate 1820envelopes rather than just one, but the option to have a gated amplifier is 1821still there. In addition glide and noise were added, both of which were not in 1822the original instrument. With respect to the original instrument this was 1823perhaps not a wise move, but there seemed little point in making another Juno 1824with a different layout. The net results is that the two synths do sound quite 1825different. The emulation does not have an arpeggiator. 1826 1827 Volume: Master volume of the instrument 1828 1829 Glide: length of portamento 1830 1831 Tune: Master tuning of instrument 1832 1833 Bend: Amount of pitch wheel that is applied to the oscillators frequency. 1834 1835 1836 VCO section: 1837 1838 Octave: What octave the instrument's keyboard is in. 1839 1840 Wave: Waveform selection: Triangle, Saw, Pulse and Pulsewidth 1841 1842 PW PWM: Amount of Pulsewidth (when Pulse is selected) and Pulsewidth 1843 Modulation (When Pulsewidth is selected). 1844 1845 Freq: Frequency of PW/PWM 1846 1847 OFF/SUB1/SUB2; Adds a square sub-oscillator either off, 1 or 2 octaves 1848 down from a note. 1849 1850 MG (Modulation Group): 1851 1852 Freq: Frequency of LFO 1853 1854 Delay: Amount of time before the LFO affects the destination when a key 1855 is pressed. 1856 Level: How strongly the LFO affects the destination 1857 1858 VCO/VCF/VCA: Destinations that the LFO can go to: 1859 1860 VCO: The Voltage Controlled Oscillator: 1861 Affects oscillator pitch, producing vibrato 1862 1863 VCF: The Voltage Controlled Filter: 1864 Affects Filter, producing a wah effect 1865 1866 VCA: The Voltage Controlled Amplifier: 1867 Affects the Amplifier, producing tremolo 1868 1869 VCF section: 1870 1871 Freq: Cut off frequency of the filter 1872 1873 Res: Resonance of the filter 1874 1875 Env: By how much the filter is affected by the envelope. 1876 1877 Kbd: How much Keyboard tracking is applied to the envelope. note: 1878 1879 A low setting doesn't allow the filter to open, making the notes 1880 seem darker the further you go up the keyboard. 1881 1882 Hold: prevent key off events 1883 1884 Mono Mode: Gang all voices to a single 'fat' monophonic synthesiser. 1885 1886 Poly: One voice per note. 1887 1888 Envelope Section: 1889 1890 Top: 1891 1892 Filter envelope: 1893 1894 Attack: Amount of time it takes the filter to fully open. 1895 A high value can produce a 'sweeping filter' effect. 1896 Decay: Amount of time it takes for the filter to close to 1897 the sustain level 1898 Sustain: Amount of filter that is sustained when a key is held 1899 1900 Release: Amount of time it takes for the filter envelope to stop 1901 affecting the filter. Combining a low filter release with a 1902 high amplitude release time can cause an interesting effect. 1903 1904 Bottom: 1905 1906 Amplitude envelope: 1907 1908 Attack: Amount of time it takes for the signal to reach its peak. 1909 1910 Decay: Amount of time it takes for the signal to drop to the 1911 sustain level 1912 Sustain: How quickly the sound decays to silence. 1913 1914 Release: How long it takes the sound to decay to silence after 1915 releasing a key. 1916 1917 VCA: 1918 1919 Env: When on, this causes the Amplitude envelope to affect the sound. 1920 I.E, If you have a long attack time, you get a long attack time. 1921 Gate: When on, this causes the Amplitude envelope only (not the filter 1922 envelope) to be be bypassed. 1923 Gain: Gain of signal. 1924 1925 Effects Section: 1926 1927 0: No effects 1928 1: Soft Chorus 1929 2: Phaser 1930 3: Ensemble 1931 1932 Intensity: How much the effects affect the output. 1933 1934There are some mildly anomolous effects possible from the MG section, especially 1935with the VCA. The MG and the env are summed into the VCA which means if the env 1936decays to zero then the LFO may end up pumping the volume, something that may 1937be unexpected. Similarly, if the LFO is pumping and the voice finally stops its 1938cycle then the closing gate may cause a pop on the MG signal. These can be 1939resolved however the current behavious is probably close to the original. 1940 1941Bristol thanks Andrew Coughlan for patches, bug reports, this manual page and 1942diverse suggestions to help improve the application. 1943 1944Korg in no way endorses this emulation of their classic synthesiser and have 1945their own emulation product that gives the features offered here. Korg, 1946Mono/Poly, Poly-6, MS-20, Vox and Continental are all registered names or 1947trademarks of Korg Inc of Japan. 1948 1949 1950 1951 1952 ARP AXXE 1953 -------- 1954 1955TBD 1956 1957At the risk of getting flamed, this is potentially the ugliest synth ever made, 1958although the competition is strong. It was implemented as a build up to the far 1959more useful ARP 2600 to understand the ARP components and their implementation. 1960 1961The implementation is a giveaway written during a week long business trip to 1962Athens to keep me busy in the hotel. Its design lead on to the Odyssey and that 1963was the step towards the final big brother, the ARP 2600. 1964 1965 1966 1967 1968 ARP ODYSSEY 1969 ----------- 1970 1971Ring modulation is correct here, it is a multiplier. This deviates from the 1972original instrument that used an XOR function on the pulsewave outputs of the 1973two oscillators. The implementation has two models, Mark-I and Mark-II. These 1974implement different filters as per the original. Although their characteristics 1975are different it is not suggested they are a particularly close emulation of 1976the original. 1977 1978TBD 1979 1980 1981 1982 1983 Memory Moog 1984 ----------- 1985 1986TBD. 1987 1988This is actually a lot warmer than the Mini emulator, largely due to being 1989later code. The mini should be revisited but I am saving that pleasure for when 1990some more filters are available. [This was done during the 0.20 stream using the 1991Houvilainen filters and bandwidth limited oscillators to produce a far richer 1992sound. Also incorporate a number of fixes to the emulation stages.]. 1993 1994 1995 1996 1997 ARP 2600 1998 -------- 1999 2000This synth will probably never get a writeup, it is kind of beyond the scope of 2001this document. There are some discrepancies with the original: 2002 2003The filters do not self oscillate, they require an input signal. The output 2004stage is global to all voices so cannot be patched back into the signal path. 2005The original did not have a chorus, only a spring reverb. The input stage has 2006not been tested for either signal nor envelope following code. The voltage 2007manipulators were not in the first bristol upload with this emulation (-60), 2008but a future release will include mixing inverters, a lag processor, and 2009possibly also a Hz->V extractor. The unit has an extra LFO where the original 2010had just a clock trigger circuit, it produces a TRI wave, can be used to 2011trigger the AR envelope and be used for modulation. The electroswitch is 2012unidirectional, two inputs switchable to one output. The sample and hold 2013circuit cannot accept an external clock. The Keyboard inputs to the VCO cannot 2014accept and alternative signal other than the MIDI note with tracking of this 2015note either enabled or disabled. 2016 2017The rest works, ie, all the VCO/VCF/VCA/ENV/AMP and any of the 30 or so outputs 2018can be repatched into any of the 50 or so inputs. Patches cause no overhead in 2019the engine as it uses default buffering when not repatched, so feel free to put 2020in as many cables as you can fit. Patches in the GUI still demand a lot of CPU 2021cycles. Release -77 improved this about 5-fold and further improvements are in 2022the pipeline: the 0.10 stream implemented color caching and XImage graphics 2023interface which massively improved GUI performance. 2024 2025 2026 2027 2028 REALISTIC MG-1 CONCERTMATE 2029 -------------------------- 2030 2031This is a pimpy little synth. It was sold through the Realistic electronics 2032chain, also known as Radio Shack (and as Tandy, in the UK at least). It was 2033relatively cheap but had a design from Moog Music (from after Robert Moog 2034had left?) including the patented ladder filter. It consisted of a monophonic 2035synth, dual oscillator, lfo, noise, filter, env, and a ring modulator. On top 2036of that there was an organ circuit to give 'polyphony'. It was not really 2037polyphonic although different descriptions will tell you it had 10 voices. 2038These write-ups are by people who probably only had 10 fingers, the truth is 2039that the organ circuit was as per any other - it had a master oscillator at 2040about 2MHz and this was divided using binary counters to deliver a frequency 2041for every note. The output of the 'poly' section was lamentable at best, it is 2042a fairly pure square wave passed through the filter and contour. This is fully 2043emulated although in addition to the contour bristol implements a per note 2044envelope just to groom the note - this prevents ticks when new keys are pressed 2045with the mono envelope fully open. There is no access to this env, it just has 2046fast attack and decay times to smooth the signal and is preconfigured by the 2047user interface on startup. 2048 2049The mono section is reasonably fun, the oscillators can be synchronised and 2050there is a ring modulator so the range of sounds is quite wide. The emulator 2051uses a chaimberlain filter so is not as warm as the Moog ladder filters. 2052 2053The list of people who used this is really quite amazing. The promotion for 2054the product had Elton John holding one up in the air, although seeing as he 2055probably already had every other synth known to man, holding it up in the 2056air is likely to be all he ever did with it. Who knows how much they had to 2057pay him to do it - the photo was nice though, from the days when Elton was 2058still bald and wearing ridiculously oversized specs. 2059 2060Tuning: 2061 2062 One control each for the poly oscillator and mono oscillators 2063 2064Glide: 2065 2066 Only affects the monophonic oscillators. 2067 2068Modulation: 2069 2070 One LFO with rate and waveshape selection 2071 produces tri, square and S/H signals. 2072 can trigger the envelope 2073 One noise source. 2074 The modulation can be directed to: 2075 Oscillators for vibrato 2076 Filter for wah-wah effects 2077 2078Oscillator-1: 2079 2080 Tri or square wave 2081 Octave from -2 to 0 transposition 2082 Sync selector (synchronises Osc-2 to Osc-1) 2083 2084Oscillator-2: 2085 2086 Tri or pulse wave 2087 Detune. This interoperates with the sync setting to alter harmonics 2088 Octave from -1 to +1 transposition 2089 2090Contour: This is not an ADSR, rather an AR envelope 2091 2092 Sustain: AR or ASR envelope selector. 2093 Tracking: controls mono oscillators 2094 Envelope control 2095 Key tracking (gate, no env) 2096 Continuous (always on) 2097 Rise (attack time) 2098 Fall (release time) 2099 2100Filter: 2101 2102 Cutoff frequency 2103 Emphasis 2104 Contour depth 2105 Keyboard tracking off, 1/2, full. 2106 2107Mixer: Levels for 2108 Mono Osc-1 2109 Mono Osc-2 2110 Noise 2111 RingMod of the mono oscillators (called 'bell'). 2112 Poly Osc level. 2113 2114Master Volume control. 2115 2116One extra button was added to save the current settings. For the rest the 2117controls reflect the simplicity of the original. The implementation is a single 2118synth, however due to the engine architecture having a pre-operational routine, 2119a post-operational routine and an operate(polyphonic emulator) the emulation 2120executes the mono synth in the pre- and post- ops to be mono, these are called 2121just once per cycle. The poly synth is executed in the operate() code so is 2122polyphonic. This leads to one minor deviation from the original routing in 2123that if you select continuous tone controls then you will also hear one note 2124from the poly section. This is a minor issue as the poly oscillator can be 2125zeroed out in the mixer. 2126 2127It is noted here that this emulation is just a freebie, the interface is kept 2128simple with no midi channel selection (start it with the -channel option and 2129it stays there) and no real memories (start it with the -load option and it 2130will stay on that memory location). There is an extra button on the front 2131panel (a mod?) and pressing it will save the current settings for next time 2132it is started. I could have done more, and will if people are interested, but 2133I built it since the current developments were a granular synth and it was 2134hard work getting my head around the grain/wave manipulations, so to give 2135myself a rest I put this together one weekend. The Rhodesbass and ARP AXXE 2136were done for similar reasons. I considered adding another mod button, to make 2137the mono section also truly polyphonic but that kind of detracts from the 2138original. Perhaps I should put together a Polymoog sometime that did kind of 2139work like that anyway. 2140 2141This was perhaps a strange choice, however I like the way it highlights the 2142difference between monophonic, polyphonic and 'neopolyphonic' synthesised 2143organs (such as the polymoog). Its a fun synth as well, few people are likely 2144to every bother buying one as they cost more now than when they were produced 2145due to being collectable: for the few hundred dollars they would set you back 2146on eBay you can get a respectable polyphonic unit. 2147So here is an emulator, for free, for those who want to see how they worked. 2148 2149 2150 2151 2152 Vox Continental 300 2153 ------------------- 2154 2155There is an additional emulator for the later Mark-II, Super, 300 or whatever 2156model you want to call it. This is probably closest to the 300. It was a 2157dual manual organ, the lower manual is a Continental and the upper manual had 2158a different drawbar configuration, using 8', 4' and 2', another two compound 2159drawbars that represented 5-1/3'+1-3/5', and 2-2/3'+2'+1' respectively. This 2160gave upper manual a wider tonic range, plus it had the ability to apply some 2161percussive controls to two of the drawbars. Now, depending on model, some of 2162these values could be different and bristol does not emulate all the different 2163combinations, it uses the harmonics described above and applies percussive to 2164the 2' and 5-1/3' harmonics (which is arguably incorrect however it gives 2165a wider combination of percussive harmonics). 2166 2167The percussive has 4 controls, these are selectors for the harmonics that will 2168be driven through the percussive decay (and then no longer respond to the 2169drawbars), a decay rate called 'L' which acts as a Longer decay when selected, 2170and a volume selector called 'S' which stands for Soft. The variables are 2171adjustable in the mods section. The mods panel is intended to be hidden as 2172they are just variable parameters. On the original units these were PCB mounted 2173pots that were not generally accessible either. The panel is visible when you 2174turn the power control off, not that I suppress the keyboard or anything when 2175the power is off, but it gave me something useful do to with this button. The 2176transparency layer is fixed here and is used to apply some drop shadow and a 2177few beer spills on the cover. 2178 2179There is an additional Bass section for those who bought the optional Bass 2180pedals (my old one had them). The emulation allow the selection of Flute and 2181Reed strengths, and to select 8' or 8'/16' harmonics. The 'Sustain' control 2182does not currently operate (0.10.9) but that can be fixed if people request 2183the feature. 2184 2185The lower manual responds to the MIDI channel on which the emulation was 2186started. The upper manual responds to notes greater than MIDI key 48 on the 2187next channel up. The Bass section also responds to this second channel on keys 2188lower than #48. Once started you cannot change the midi channel - use the 2189'-channel' option at startup to select the one you want. The actual available 2190max is 15 and that is enforced. 2191 2192The emulation only contains 6 available presets and a 'Save' button that you 2193need to double click to overwrite any preset. The emulation actually uses 2194banks, so if you started it with '-load 23' it would start up by selecting 2195bank 20, and load memory #3 from that bank. Any saved memories are also then 2196written back to bank 20, still with just 6 memories accessible 20-25. You can 2197access more via MIDI bank select and program change operations if suitably 2198linked up. 2199 2200Vox is a trade name owned by Korg Inc. of Japan, and Continental is one of 2201their registered trademarks. Bristol does not intend to infringe upon these 2202registered names and Korg have their own remarkable range of vintage emulations 2203available. You are directed to their website for further information of true 2204Korg products. 2205 2206 2207 2208 2209 Roland Jupiter 8 2210 ---------------- 2211 2212This emulator is anticipated in 0.20.4. 2213 2214The Jupiter synthesizers were the bigger brothers of the Juno series: their 2215capabilities, sounds and prices were all considerably larger. This is the 2216larger of the series, the others being the -4 and -6. The -6 and the rack 2217mounted MKS-80 both came out after the Jupiter-8 and had somewhat more flexible 2218features. Several of these have been incorporated into the emulation and that 2219is documented below. 2220 2221A quick rundown of the synth and emulation: 2222 2223The synth runs as two layers, each of which is an independent emulator running 2224the same algorithm, both layers are controlled from the single GUI. The layers 2225are started with a set of voices, effectively 4+4 per default however bristol 2226plays with those numbers to give the split/layer at 4 voices each and the 'All' 2227configuration with 8 voices - it juggles them around depending on the Poly 2228mode you select. You can request a different number of voices and the emulator 2229will effectively allocate half the number to each layer. If you request 32 2230voices you will end up with 4+4 though since 32 is interpreted as the default. 2231 2232The Poly section is used to select between Dual layers, Split keyboard and the 22338voice 'All' mode. You can redefine the split point with a double click on the 2234'Split' button and then pressing a key. If you have linked the GUI up to the 2235MIDI you should be able to press a key on your master keyboard rather than on 2236the GUI. 2237 2238After that you can select the layer as upper or lower to review the parameter 2239settings of each layer: they are as follows: 2240 2241LFO: 2242 Frequency 2243 Delay 2244 Waveform (tri, saw, square, s&h) 2245 2246VCO Mods: 2247 LFO and ENV-1 2248 Destination to modulate frequency of DCO1, DCO2 or both. 2249 2250PWM: 2251 PW 2252 PWM 2253 Modified by Env-1 or LFO 2254 2255DCO-1: 2256 Crossmod (FM) from DCO2 to DCO1 2257 Modified by Env-1 2258 2259 Octave range 16' to 2' (all mixable) 2260 Waveform: Tri, saw, pulse, square (all mixable) 2261 2262DCO-2: 2263 Sync (1->2 or 2->1 or off) 2264 Range: 32' to 2' (all mixable) 2265 Tuning 2266 Waveform: tri, saw, pulse, noise (all mixable) 2267 2268Mix: 2269 Osc 1 and Osc 2 2270 2271HPF: 2272 High pass filter of signal 2273 2274Filter: 2275 Cutoff 2276 Emphasis 2277 LPF/BPF/HPF 2278 Env modulation 2279 Source from Env-1 or Env-2 2280 LFO mod amount 2281 Keyboard tracking amount 2282 2283VCA: 2284 Env-2 modulation 2285 LFO modulation 2286 2287ADSR-1: 2288 A/D/S/R 2289 Keyboard tracking amount 2290 Invert 2291 2292ADSR-2: 2293 A/D/S/R 2294 Keyboard tracking amount 2295 2296Pan: 2297 Stereo panning of layer 2298 2299All of the above 40 or so parameters are part of the layer emulation and are 2300separately configurable. 2301 2302The keyboard can operate in several different modes which are selectable from 2303the Poly and Keyboard mode sections. The first main one is Dual, Split and All. 2304Dual configure the two synth layers to be placed on top of each other. Split 2305configures them to be next to each other and by double clicking the split 2306button you can then enter a new split point by pressing a key. The All setting 2307gives you a single layer with all 8 voices active. These settings are for the 2308whole synth. 2309 2310The Poly section provides different playing modes for each layer independently. 2311There are 3 settings: Solo give the layer access to a single voice for playing 2312lead solos. Unison give the layer however many voices it is allowed (8 if in 2313the All mode, 4 otherwise) and stacks them all on top of each other. This is 2314similar to Solo but with multiple voices layered onto each other. Unison is 2315good for fat lead sounds, Solo better for mono bass lines where Unison might 2316have produced unwanted low frequency signal phasing. The third option is Poly 2317mode 1 where the synth allocates a single voice to each key you press. The 2318original also had Poly mode 2 which was not available at the first bristol 2319release - this mode would apply as many notes as available to the keys you 2320pressed: 1 key = 8 voices as in Unison, with 2 keys pressed each would get 4 2321voices each, 4 keys pressed would get 2 voices and mixtures in there for other 2322key combinations. This may be implemented in a future release but it is a 2323rather left field option and would have to be put into the MIDI library that 2324controls the voice assignments. 2325 2326The arpeggiator integrated into bristol is a general design and will differ 2327from the original. The default settings are 4 buttons controlling the range 2328of the arpeggiation, from 1 to 4 octaves, 4 buttons controlling the mode as 2329Up, Down, Up+Down or Random sequencing of the notes available, and 4 notes 2330that are preloaded into the sequence. 2331 2332Finally there are two global controls that are outside of the memories - the 2333rate and clock source (however externally driven MTC has not been implemented 2334yet). It is noted that the Arpeggiator settings are separate from the sequence 2335information, ie, Up/Down/Rnd, the range and the arpeggiator clock are not the 2336same as the note memory, this is discussed further in the memory setting 2337section below. 2338 2339It is possible to redefine the arpeggiator sequence: select the function 2340button on the right hand side, then select any of the arpeggiator mode buttons, 2341this will initiate the recording. It does not matter which of the mode is 2342selected since they will all start the recording sequence. When you have 2343finished then select the mode button again (you may want to clear the function 2344key if still active). You can record up to 256 steps, either from the GUI 2345keyboard or from a master controller and the notes are saved into a midi 2346key memory. 2347 2348There is no capability to edit the sequences once they have been entered, that 2349level of control is left up to separate MIDI sequencers for which there are 2350many available on Linux. Also, the note memory is actually volatile and will 2351be lost when the emulation exits. If you want to save the settings then you 2352have to enter them from the GUI keyboard or make sure that the GUI is linked 2353up to the master keyboard MIDI interface - you need to be able to see the 2354GUI keyboard following the notes pressed on the master keyboard since only 2355when the GUI sees the notes can it store them for later recall. If the GUI 2356did view the sequence entered here then it will be saved with the patch in 2357a separate file (so that it can be used with other bristol synths). 2358 2359In addition to the Arpeggiator there is the 'Chord' control. The original 2360synth had two green panel buttons labelled 'Hold', they were actually similar 2361to the sustain pedal on a MIDI keyboard or piano, with one for each layer of 2362the synth. They have been redefined here as Chord memory. When activated the 2363layer will play a chord of notes for every key press. The notes are taken from 2364separate chord memory in the Arpeggiator sequencer. The result is very similar 2365to the Unison mode where every voice is activated for a single key, the 2366difference here is that every voice may be playing a different note to give 2367phat chords. To configure a chord you enable the function key and the target 2368Hold button to put the synth into chord learning mode, play a set of notes 2369(you don't have to hold them down), and click again to finalise the chord. 2370If there are more chord notes than voices available then all voices will 2371activate. If there are more voices than notes then you will be able to play 2372these chord polyphonically, for example, if you have 8 voices and entered 2373just 4 chorded notes then you will have 2 note polyphony left. You should 2374also be able to play arpeggiations of chords. The maximum number of notes 2375in a chord is 8. 2376 2377The synth has a modifier panel which functions as performance options which 2378can be applied selectively to different layers: 2379 2380 Bender: 2381 This is the depth of the settings and is mapped by the engine to 2382 continuous controller 1 - the 'Mod' wheel. The emulation also tracks 2383 the pitch wheel separately. 2384 2385 Bend to VCO 2386 This applies an amount of pitch bend from the Mod wheel selectively 2387 to either VCO-1 and/or VCO-2. These settings only affect the Mod 2388 layers selected from the main panel. Subtle modifications applied in 2389 different amounts to each oscillator can widen the sound considerable 2390 by introducing small amounts of oscillator phasing. 2391 2392 Bend to VCF 2393 Affects the depth of cutoff to the filter with on/off available. Again 2394 only applies to layers activate with the Mod setting. 2395 2396 LFO to VCO: 2397 The mod panel has a second global LFO producing a sine wave. This can 2398 be driven in selectable amounts to both VCO simultaneously. Layers are 2399 selected from the Mod buttons. 2400 2401 LFO to VCF: 2402 The LFO can be driven in selectable amounts to both VCO or to the VCF. 2403 Layers are selected from the Mod buttons. 2404 2405 Delay: 2406 This is the rise time of the LFO from the first note pressed. There is 2407 no apparent frequency control of the second LFO however bristol allows 2408 the frequency and gain of the LFO to track velocity using function B4 2409 (see below for function settings). Since there is only one LFO per 2410 emulation then the velocity tracking can be misleading as it only 2411 tracks from a single voice and may not track the last note. For this 2412 reason it can be disabled. Using a tracking from something like channel 2413 pressure is for future study. 2414 2415 Glide: 2416 Glissando between key frequencies, selectable to be either just to the 2417 upper layer, off, or to both layers. 2418 2419 Transpose: 2420 There are two transpose switches for the lower and upper layers 2421 respectively. The range is +/1 one octave. 2422 2423Modifier panel settings are saved in the synth memories and are loaded with 2424the first memory (ie, with dual loaded memories discussed below). The ability 2425to save these settings in memory is an MKS-80 feature that was not available 2426in either the Jupiter-6 or -8. 2427 2428There are several parts to the synth memories. Layer parameters govern sound 2429generation, synth parameters that govern operating modes such Dual/Split, 2430Solo/Unison etc, Function settings that modify internal operations, the 2431parameters for the mod panel and finally the Arpeggiator sequences. These 2432sequences are actually separate from the arpeggiator settings however that 2433was covered in the notes above. 2434 2435When a patch is loaded then only the layer parameters are activated so that the 2436new sound can be played, and the settings are only for the selected layer. This 2437means any chord or arpeggiation can be tried with the new voice active. 2438 2439When a memory is 'dual loaded' by a double click on the Load button then all 2440the memory settings will be read and activated: the current layer settings, 2441synth settings, operational parameters including the peer layer parameters 2442for dual/split configurations. Dual loading of the second layer will only 2443happen if the memory was saved as a split/double with a peer layer active. 2444 2445The emulation adds several recognised Jupiter-6 capabilities that were not a 2446part of the Jupiter-8 product. These are 2447 2448 1. PW setting as well as PWM 2449 2. Cross modulation can be amplified with envelope-1 for FM type sounds 2450 3. Sync can be set in either direction (DCO1 to 2 or DCO2 to 1) 2451 4. The waveforms for DCO 1&2 are not exclusive but mixable 2452 5. The LFO to VCA is a continuous controller rather than stepped 2453 6. The envelope keyboard tracking is continuous rather than on/off 2454 7. The filter option is multimode LP/BP/HP rather than 12/24dB 2455 8. Layer detune is configurable 2456 9. Layer transpose switches are available 2457 10. Arpeggiator is configurable on both layers 2458 2459Beyond these recognised mods it is also possible to select any/all DCO 2460transpositions which further fattens up the sound as it allows for more 2461harmonics. There is some added detune between the waveforms with its depth 2462being a function of the -detune setting. Separate Pan and Balance controls 2463have been implemented, Pan is the stereo positioning and is configurable per 2464layer. Balance is the relative gain between each of the layers. 2465 2466There are several options that can be configured from the 'f' button 2467in the MIDI section. When you push the f(n) button then the patch and bank 2468buttons will not select memory locations but display the on/off status of 16 2469algorithmic changes to the emulation. Values are saved in the synth memories. 2470These are bristol specific modifications and may change between releases unless 2471otherwise documented. 2472 2473F(n): 2474 2475 f(p1): Env-1 retriggers 2476 f(p2): Env-1 conditionals 2477 f(p3): Env-1 attack sensitivity 2478 f(p4): Env-2 retriggers 2479 f(p5): Env-2 conditionals 2480 f(p6): Env-2 attack sensitivity 2481 f(p7): Noise per voice/layer 2482 f(p8): Noise white/pink 2483 2484 f(b1): LFO-1 per voice/layer 2485 f(b2): LFO-1 Sync to Note ON 2486 f(b3): LFO-1 velocity tracking 2487 f(b4): Arpeggiator retrigger 2488 f(b5): LFO-2 velocity tracking 2489 f(b6): NRP enable 2490 f(b7): Debug MIDI 2491 f(b8): Debug GUI controllers 2492 2493The same function key also enables the learning function of the arpeggiator 2494and chord memory, as explained above. When using the arpeggiator you may want 2495to test with f(b4) enabled, it will give better control of the filter envelope. 2496 2497 2498Other differences to the original are the Hold keys on the front panel. These 2499acted as sustain pedals however for the emulation that does not function very 2500well. With the original the buttons were readily available whilst playing and 2501could be used manually, something that does not work well with a GUI and a 2502mouse. For this reason they were re-used for 'Unison Chording' discussed above. 2503Implementing them as sustain pedals would have been an easier if less flexible 2504option and users are advised that the bristol MIDI library does recognise the 2505sustain controller as the logical alternative here. 2506 2507Another difference would be the quality of the sound. The emulation is a lot 2508cleaner and not as phat as the original. You might say it sounds more like 2509something that comes from Uranus rather than Jupiter and consideration was 2510indeed given to a tongue in cheek renaming of the emulation..... The author is 2511allowed this criticism as he wrote the application - as ever, if you want the 2512original sound then buy the original synth (or get Rolands own emulation?). 2513 2514A few notes are required on oscillator sync since by default it will seem to 2515be quite noisy. The original could only product a single waveform at a single 2516frequency at any one time. Several emulators, including this one, use a bitone 2517oscillator which generates complex waveforms. The Bristol Bitone can generate 2518up to 4 waveforms simultaneously at different levels for 5 different harmonics 2519and the consequent output is very rich, the waves can be slightly detuned, 2520the pulse output can be PW modulated. As with all the bristol oscillators that 2521support sync, the sync pulse is extracted as a postive leading zero crossing. 2522Unfortunately if the complex bitone output is used as input to sync another 2523oscillator then the result is far too many zero crossings to extract a good 2524sync. For the time being you will have to simplify the sync source to get a 2525good synchronised output which itself may be complex wave. A future release 2526will add a sync signal from the bitone which will be a single harmonic at the 2527base frequency and allow both syncing and synchronised waveform outputs to be 2528arbitrary. 2529 2530 2531 2532 2533 CRUMAR BIT-1, BIT-99, BIT-100 2534 ----------------------------- 2535 2536I was considering the implementation of the Korg-800, a synth I used to borrow 2537without having due respect for it - it was a late low cost analogue having 2538just one filter for all the notes and using the mildly annoying data entry 2539buttons and parameter selectors. Having only one filter meant that with key 2540tracking enabled the filter would open up as different keys were pressed, 2541wildly changing the sound of active notes. Anyway, whilst considering how to 2542implement the entry keys (and having features like the mouse tracking the 2543selectors of the parameter graphics) I was reminded of this synthesizer. It 2544was developed by Crumar but released under the name 'Bit' as the Crumar name 2545was associated with cheesy roadrunner electric pianos at the time (also 2546emulated by Bristol). This came out at the same time as the DX-7 but for 2547half the price, and having the split and layer facilities won it several awards 2548that would otherwise have gone to the incredibly innovative DX. However with 2549the different Crumar models being released as the digital era began they kind 2550of fell between the crack. It has some very nice mod features though, it was 2551fun to emulate and hopefully enjoyable to play with. 2552 2553As a side note, the Korg Poly-800 is now also emulated by bristol 2554 2555A quick rundown of the Bit features are below. The different emulated models 2556have slightly different default parameter values and/or no access to change 2557them: 2558 2559 Two DCO with mixed waveforms. 2560 VCF with envelope 2561 VCA with envelope 2562 Two LFO able to mod all other components, controlled by the wheel and key 2563 velocity, single waveform, one had ramp and the other sawtooth options. 2564 2565The envelopes were touch sensitive for gain but also for attack giving plenty 2566of expressive capabilities. The bristol envelope, when configured for velocity 2567sensitive parameters (other than just gain) will also affect the attack rate. 2568 2569The front panel had a graphic that displayed all the available parameters and 2570to change then you had to select the "Address" entry point then use the up/down 2571entry buttons to change its value. Bristol uses this with the addition that the 2572mouse can click on a parameter to start entering modifications to it. 2573 2574The emulation includes the 'Compare' and 'Park' features although they are a 2575little annoying without a control surface. They work like this (not quite the 2576same as the original): When you select a parameter and change it's value then 2577the changes are not actually made to the active program, they just change the 2578current sounds. The Compare button can be used to flip between the last loaded 2579value and the current modified one to allow you to see if you prefer the sound 2580before or after the modification. 2581 2582If you do prefer the changes then to keep them you must "Park" them into the 2583running program before saving the memory. At the time of writing the emulation 2584emulated the double click to park&write a memory, however it also has an actual 2585Save button since 'Save to Tape' is not a feature here. You can use park and 2586compare over dual loaded voices: unlike the original, which could only support 2587editing of sounds when not in split/double, this emulation allows you to edit 2588both layers by selecting the upper/lower entry buttons and then using the 2589sensitive panel controls to select the addressed parameters. This is not the 2590default behaviour, you first have to edit address 102 and increment it. Then, 2591each layer can be simultaneously edited and just needs to be parked and saved 2592separately. The Park/Compare cache can be disabled by editing parameter DE 101, 2593changes are then made to the synth memory and not the cache. 2594 2595The memories are organised differently to the original. It had 99 memories, and 2596the ones from 75 and above were for Split and Layered memories. Bristol can 2597have all memories as Split or Layer. When you save a memory it is written to 2598memory with a 'peer' program locator. When you load it with a single push on 2599the Load button it returns to the active program, but if you double click then 2600its 'peer' program is loaded into the other layer: press Load once to get the 2601first program entered, then press it again - the Split/Layer will be set to 2602the value from the first program and the second layer will be loaded. This 2603naturally requires that the first memory was saved with Split/Layer enabled. 2604It is advised (however not required) that this dual loading is done from the 2605lower layer. This sequence will allow the lower layer to configure certain 2606global options that the upper layer will not overwrite, for example the layer 2607volumes will be select from the lower layer when the upper layer is dual 2608loaded. 2609 2610For MIDI program change then since this quirky interface cannot be emulated 2611then the memories above 75 will be dual loaded, the rest will be single loaded. 2612 2613Bristol will also emulate a bit-99 and a Bit-99m2 that includes some parameter 2614on the front panel that were not available on the original. The engine uses the 2615exact same algorithm for all emulations but the GUI presents different sets of 2616parameters on the front panel. Those that are not displayed can only be accessed 2617from the data entry buttons. The -99m2 put in a few extra features (ie, took a 2618few liberties) that were not in the original: 2619 2620 DCO adds PWM from the LFO, not in the original 2621 DCO-2 adds Sync to DCO-1, also not in the original 2622 DCO-2 adds FM from DCO-1 2623 DCO add PWM from Envelope 2624 Glide has been added 2625 DCO harmonics are not necessarily exclusive 2626 Various envelope option for LFO 2627 S&H LFO modulation 2628 2629The reason these were added was that bristol could already do them so were 2630quite easy to incorporate, and at least gave two slightly different emulations. 2631 2632The oscillators can work slightly differently as well. Since this is a purely 2633digital emulations then the filters are a bit weak. This is slightly compensated 2634by the ability to configure more complex DCO. The transpose selectors (32', 16', 26358' and 2') were exclusive in the original. That is true here also, however if 2636controllers 84 and 85 are set to zero then they can all work together to fatten 2637out the sound. Also, the controllers look like boolean however that is only the 2638case if the data entry buttons are used, if you change the value with the data 2639entry pot then they act more like continuous drawbars, a nice effect however 2640the display will not show the actual value as the display remains boolean, you 2641have to use your ear. The square wave is exclusive and will typically only 2642function on the most recently selected (ie, typically highest) harmonic. 2643 2644The same continuous control is also available on the waveform selectors. You 2645can mix the waveform as per the original however the apparent boolean selectors 2646are again continuous from 0.0 to 1.0. The net result is that the oscillators 2647are quite Voxy having the ability to mix various harmonic levels of different 2648mixable waveforms. 2649 2650The stereo mode should be correctly implemented too. The synth was not really 2651stereo, it had two outputs - one for each layer. As bristol is stereo then each 2652layer is allocated to the left or right channel. In dual or split they came 2653out separate feeds if Stereo was selected. This has the rather strange side 2654effect of single mode with 6 voices. If stereo is not selected then you have 2655a mono synth. If stereo is selected then voices will exit from a totally 2656arbitrary output depending on which voices is allocated to each note. 2657In contrast to the original the Stereo parameter is saved with the memory and 2658if you dual load a split/layer it is taken from the first loaded memory only. 2659The implementation actually uses two different stereo mixes selectable with the 2660Stereo button: Mono is a centre pan of the signal and Stereo pans hardleft and 2661hardright respectively. These mixes can be changed with parameters 110 to 117 2662using extended data entry documented below. 2663 2664The default emulation takes 6 voices for unison and applies 3+3 for the split 2665and double modes. You can request more, for example if you used '-voices 16' 2666at startup then you would be given 8+8. As a slight anomaly you cant request 32 2667voices - this is currently interpreted as the default and gives you 3+3. 2668 2669The bit-1 did not have the Stereo control - the controller presented is the 2670Unison button. You can configure stereo from the extended data entry ID 110 and 2671111 which give the LR channel panning for 'Mono' setting, it should default to 2672hard left and right panning. Similarly the -99 emulations do not have a Unison 2673button, the capability is available from DE 80. 2674 2675The memories for the bit-1 and bit-99 should be interchangeable however the 2676code maintains separate directories. 2677 2678There are three slightly different Bit GUI's. The first is the bit-1 with a 2679limited parameter set as it only had 64 parameters. The second is the bit-99 2680that included midi and split options in the GUI and has the white design that 2681was an offered by Crumar. The third is a slightly homogenous design that is 2682specific to bristol, similar to the black panelled bit99 but with a couple of 2683extra parameters. All the emulations have the same parameters, some require you 2684use the data entry controls to access them. This is the same as the original, 2685there were diverse parameters that were not in memories that needed to be 2686entered manually every time you wanted the feature. The Bristol Bit-99m2 has 2687about all of the parameters selectable from the front panel however all of the 2688emulations use the same memories so it is not required to configure them at 2689startup (ie, they are saved). The emulation recognises the following parameters: 2690 2691 Data Entry 1 LFO-1 triangle wave selector (exclusive switch) 2692 Data Entry 2 LFO-1 ramp wave selector (exclusive switch) 2693 Data Entry 3 LFO-1 square wave selector (exclusive switch) 2694 Data Entry 4 LFO-1 route to DCO-1 2695 Data Entry 5 LFO-1 route to DCO-2 2696 Data Entry 6 LFO-1 route to VCF 2697 Data Entry 7 LFO-1 route to VCA 2698 Data Entry 8 LFO-1 delay 2699 Data Entry 9 LFO-1 frequency 2700 Data Entry 10 LFO-1 velocity to frequency sensitivity 2701 Data Entry 11 LFO-1 gain 2702 Data Entry 12 LFO-1 wheel to gain sensitivity 2703 2704 Data Entry 13 VCF envelope Attack 2705 Data Entry 14 VCF envelope Decay 2706 Data Entry 15 VCF envelope Sustain 2707 Data Entry 16 VCF envelope Release 2708 Data Entry 17 VCF velocity to attack sensitivity (and decay/release) 2709 Data Entry 18 VCF keyboard tracking 2710 Data Entry 19 VCF cutoff 2711 Data Entry 20 VCF resonance 2712 Data Entry 21 VCF envelope amount 2713 Data Entry 22 VCF velocity to gain sensitivity 2714 Data Entry 23 VCF envelope invert 2715 2716 Data Entry 24 DCO-1 32' harmonic 2717 Data Entry 25 DCO-1 16' harmonic 2718 Data Entry 26 DCO-1 8' harmonic 2719 Data Entry 27 DCO-1 4' harmonic 2720 Data Entry 28 DCO-1 Triangle wave 2721 Data Entry 29 DCO-1 Ramp wave 2722 Data Entry 30 DCO-1 Pulse wave 2723 Data Entry 31 DCO-1 Frequency 24 semitones 2724 Data Entry 32 DCO-1 Pulse width 2725 Data Entry 33 DCO-1 Velocity PWM 2726 Data Entry 34 DCO-1 Noise level 2727 2728 Data Entry 35 DCO-2 32' harmonic 2729 Data Entry 36 DCO-2 16' harmonic 2730 Data Entry 37 DCO-2 8' harmonic 2731 Data Entry 38 DCO-2 4' harmonic 2732 Data Entry 39 DCO-2 Triangle wave 2733 Data Entry 40 DCO-2 Ramp wave 2734 Data Entry 41 DCO-2 Pulse wave 2735 Data Entry 42 DCO-2 Frequency 24 semitones 2736 Data Entry 43 DCO-2 Pulse width 2737 Data Entry 44 DCO-2 Env to pulse width 2738 Data Entry 45 DCO-2 Detune 2739 2740 Data Entry 46 VCA velocity to attack sensitivity (and decay/release) 2741 Data Entry 47 VCA velocity to gain sensitivity 2742 Data Entry 48 VCA overall gain ADSR 2743 Data Entry 49 VCA Attack 2744 Data Entry 50 VCA Decay 2745 Data Entry 51 VCA Sustain 2746 Data Entry 52 VCA Release 2747 2748 Data Entry 53 LFO-2 triangle wave selector (exclusive switch) 2749 Data Entry 54 LFO-2 saw wave selector (exclusive switch) 2750 Data Entry 55 LFO-2 square wave selector (exclusive switch) 2751 Data Entry 56 LFO-2 route to DCO-1 2752 Data Entry 57 LFO-2 route to DCO-2 2753 Data Entry 58 LFO-2 route to VCF 2754 Data Entry 59 LFO-2 route to VCA 2755 Data Entry 60 LFO-2 delay 2756 Data Entry 61 LFO-2 frequency 2757 Data Entry 62 LFO-2 velocity to frequency sensitivity 2758 Data Entry 63 LFO-2 gain 2759 Data Entry 12 LFO-2 wheel to gain sensitivity 2760 2761 Data Entry 64 Split 2762 Data Entry 65 Upper layer transpose 2763 Data Entry 66 Lower Layer gain 2764 Data Entry 67 Upper Layer gain 2765 2766The following were visible in the Bit-99 graphics only: 2767 2768 Data Entry 68 MIDI Mod wheel depth 2769 Data Entry 69 MIDI Velocity curve (0 = soft, 10=linear, 25 = hard) 2770 Data Entry 70 MIDI Enable Debug 2771 Data Entry 71 MIDI Enable Program Change 2772 Data Entry 72 MIDI Enable OMNI Mode 2773 Data Entry 73 MIDI Receive channel 2774 2775 Data Entry 74 MIDI Mem Search Upwards 2776 Data Entry 75 MIDI Mem Search Downwards 2777 Data Entry 76 MIDI Panic (all notes off) 2778 2779Most of the MIDI options are not as per the original. This is because they are 2780implemented in the bristol MIDI library and not the emulation. 2781 2782The following were added which were not really part of the Bit specifications 2783so are only visible on the front panel of the bit100. For the other emulations 2784they are accessible from the address entry buttons. 2785 2786 Data Entry 77 DCO-1->DCO-2 FM 2787 Data Entry 78 DCO-2 Sync to DCO-1 2788 Data Entry 79 Keyboard glide 2789 Data Entry 80 Unison 2790 2791 Data Entry 81 LFO-1 SH 2792 Data Entry 82 LFO-1 PWM routing for DCO-1 2793 Data Entry 83 LFO-1 PWM routing for DCO-2 2794 Data Entry 84 LFO-1 wheel tracking frequency 2795 Data Entry 85 LFO-1 velocity tracking gain 2796 Data Entry 86 LFO-1 per layer or per voice 2797 2798 Data Entry 87 LFO-2 SH 2799 Data Entry 88 LFO-2 PWM routing for DCO-1 2800 Data Entry 89 LFO-2 PWM routing for DCO-2 2801 Data Entry 90 LFO-2 wheel tracking frequency 2802 Data Entry 91 LFO-2 velocity tracking gain 2803 Data Entry 92 LFO-2 per layer or per voice 2804 2805 Data Entry 93 ENV-1 PWM routing for DCO-1 2806 Data Entry 94 ENV-1 PWM routing for DCO-2 2807 2808 Data Entry 95 DCO-1 restricted harmonics 2809 Data Entry 96 DCO-2 restricted harmonics 2810 2811 Data Entry 97 VCF Filter type 2812 Data Entry 98 DCO-1 Mix 2813 2814 Data Entry 99 Noise per layer 2815 2816 Data Entry 00 Extended data entry (above 99) 2817 2818Extended data entry is for all parameters above number 99. Since the displays 2819only have 2 digits it is not totally straightforward to enter these values and 2820they are only available in Single mode, not dual or split - strangely similar 2821to the original specification for editing memories. These are only activated for 2822the lower layer loaded memory, not for dual loaded secondaries or upper layer 2823loaded memories. You can edit the upper layer voices but they will be saved with 2824their original extended parameters. This may seem correct however it is possible 2825to edit an upper layer voice, save it, and have it sound different when next 2826loaded since the extended parameters were taken from a different lower layer. 2827This is kind of intentional but if in doubt then only ever dual load voices from 2828the lower layer and edit them in single mode (not split or layer). Per default 2829the emulation, as per the original, will not allow voice editing in Split or 2830Layer modes however it can be enabled with DE 102. 2831 2832All the Bit emulations recognise extended parameters. They are somewhat in a 2833disorganised list as they were built in as things developed. For the most part 2834they should not be needed. 2835The Bit-100 includes some in its silkscreen, for the others you can access them 2836as follows: 2837 28381. deselect split or double 28392. select addr entry 28403. use 0..9 buttons to enter address 00 28414. increment value to '1'. Last display should show EE (Extended Entry) 2842 28435. select last two digits of desired address with 0-9 buttons 28446. change value (preferably with pot). 2845 28467. when finished, select address 00 again (this is now actually 100) to exit 2847 2848 Data Entry 100 Exit extended data entry 2849 Data Entry 101 enable WriteThru scratchpad (disables park and compare) 2850 Data Entry 102 enable layer edits on Split/Double memories. 2851 Data Entry 103 LFO-1 Sync to note on 2852 Data Entry 104 LFO-2 Sync to note on 2853 Data Entry 105 ENV-1 zero retrigger 2854 Data Entry 106 ENV-2 zero retrigger 2855 Data Entry 107 LFO-1 zero retrigger 2856 Data Entry 108 LFO-2 zero retrigger 2857 Data Entry 109 Debug enable (0 == none, 5 == persistent) 2858 2859 Data Entry 110 Left channel Mono gain, Lower 2860 Data Entry 111 Right channel Mono gain, Lower 2861 Data Entry 112 Left channel Stereo gain, Lower 2862 Data Entry 113 Right channel Stereo gain, Lower 2863 Data Entry 114 Left channel Mono gain, Upper 2864 Data Entry 115 Right channel Mono gain, Upper 2865 Data Entry 116 Left channel Stereo gain, Upper 2866 Data Entry 117 Right channel Stereo gain, Upper 2867 Data Entry 118 Bit-100 flag 2868 Data Entry 119 Temperature sensitivity 2869 2870 Data Entry 120 MIDI Channel tracking layer-2 (same/different channel) 2871 Data Entry 121 MIDI Split point tracking layer-2 (same/different split) 2872 Data Entry 122 MIDI Transpose tracking (layer-2 or both layers) N/A 2873 Data Entry 123 MIDI NRP enable 2874 2875 Data Entry 130 Free Memory Search Up 2876 Data Entry 131 Free Memory Search Down 2877 Data Entry 132 ENV-1 Conditional 2878 Data Entry 133 ENV-2 Conditional 2879 Data Entry 134 LFO-1 ENV Conditional 2880 Data Entry 135 LFO-2 ENV Conditional 2881 Data Entry 136 Noise white/pink 2882 Data Entry 137 Noise pink filter (enable DE 136 Pink) 2883 Data Entry 138 Glide duration 0 to 30 seconds 2884 Data Entry 139 Emulation gain level 2885 2886 Data Entry 140 DCO-1 Square wave gain 2887 Data Entry 141 DCO-1 Subharmonic level 2888 Data Entry 142 DCO-2 Square wave gain 2889 Data Entry 143 DCO-2 Subharmonic level 2890 2891The 150 range will be incorporated when the Arpeggiator code is more stable, 2892currently in development for the Jupiter. This is anticipated in 0.20.4: 2893 2894 Data Entry 150 Arpeggiator Start/Stop 2895 Data Entry 151 Arpeggiator mode D, U/D, U or Random 2896 Data Entry 152 Arpeggiator range 1, 2, 3, 4 octaves 2897 Data Entry 153 Arpeggiator rate 2898 Data Entry 154 Arpeggiator external clock 2899 Data Entry 155 Arpeggiator retrigger envelopes 2900 Data Entry 156 Arpeggiator poly-2 mode 2901 Data Entry 157 Chord Enable 2902 Data Entry 158 Chord Relearn 2903 Data Entry 159 Sequencer Start/Stop 2904 Data Entry 160 Sequencer mode D, U/D, U or Random 2905 Data Entry 161 Sequencer range 1, 2, 3, 4 octaves 2906 Data Entry 162 Sequencer rate 2907 Data Entry 163 Sequencer external clock 2908 Data Entry 164 Sequencer retrigger envelopes 2909 Data Entry 165 Sequencer Relearn 2910 2911The following can be manually configured but are really for internal uses only 2912and will be overwritten when memories are saved to disk. The Split/Join flag, 2913for example, is used by dual loading memories to configure the peer layer to 2914load the memory in DE-198, and the stereo placeholder for configuring the stereo 2915status of any single loaded memory. 2916 2917 Data Entry 193 Reserved: save bit-1 formatted memory 2918 Data Entry 194 Reserved: save bit-99 formatted memory 2919 Data Entry 195 Reserved: save bit-100 formatted memory 2920 Data Entry 196 Reserved: Split/Join flag - internal use 2921 Data Entry 197 Reserved: Stereo placeholder - internal use 2922 Data Entry 198 Reserved: Peer memory pointer - internal use 2923 Data Entry 199 Reserved: DCO-2 Wheel mod (masks entry 12) - internal use 2924 2925The tuning control in the emulation is on the front panel rather than on the 2926rear panel as in the original. It had a keyboard sensitivity pot however that 2927is achieved separately with bristol using velocity curves from the MIDI control 2928settings. The front panel rotary defaults to 0% tuning and is not saved in the 2929memory. The front panel gain controls are also not saved in the memory and 2930default to 0.8 at startup. 2931 2932The net emulation is pretty intensive as it runs with over 150 operational 2933parameters. 2934 2935A few notes are required on oscillator sync since by default it may seem to 2936be quite noisy. The original could only produce a single waveform at a single 2937frequency at any one time. Several emulators, including this one, use a bitone 2938oscillator which generates complex waveforms. The Bristol Bitone can generate 2939up to 4 waveforms simultaneously at different levels for 5 different harmonics 2940and the consequent output is very rich, the waves can be slightly detuned, 2941the pulse output can be PW modulated. As with all the bristol oscillators that 2942support sync, the sync pulse is extracted as a postive leading zero crossing. 2943Unfortunately if the complex bitone output is used as input to sync another 2944oscillator then the result is far too many zero crossings to extract a good 2945sync. 2946Code has been implemented to generate a second sync source using a side output 2947sync wave which is then fed to a sideband sync input on the oscillator, the 2948results are far better 2949 2950 2951 2952 2953 Sequential Circuits Prophet Pro-One 2954 ----------------------------------- 2955 2956Sequential circuits released amongst the first truly polyphonic synthesisers 2957where a group of voice circuits (5 to 10 of them) were linked to an onboard 2958computer that gave the same parameters to each voice and drove the notes to 2959each voice from the keyboard. The costs were nothing short of exhorbitant and 2960this lead to Sequential releasing a model with just one voice board as a mono- 2961phonic equivalent. The sales ran up to 10,000 units, a measure of its success 2962and it continues to be recognised alongside the Mini Moog as a fat bass synth. 2963 2964The design of the Prophet synthesisers follows that of the Mini Moog. It has 2965three oscillators one of them as a dedicated LFO. The second audio oscillator 2966can also function as a second LFO, and can cross modulate oscillator A for FM 2967type effects. The audible oscillators have fixed waveforms with pulse width 2968modulation of the square wave. These are then mixed and sent to the filter with 2969two envelopes, for the filter and amplifier. 2970 2971The Pro-1 had a nice bussing matrix where 3 different sources, LFO, Filter Env 2972and Oscillator-B could be mixed in varying amounts to two different modulation 2973busses and each bus could then be chosen as inputs to modulation destinations. 2974One bus was a direct bus from the mixed parameters, the second bus was under 2975the modwheel to give configurable expressive control. 2976 2977LFO: 2978 2979 Frequency: 0.1 to 50 Hz 2980 Shape: Ramp/Triangle/Square. All can be selected, none selected should 2981 give a sine wave 2982 2983Modulations: 2984 2985 Source: 2986 2987 Filter Env amount to Direct or Wheel Mod busses 2988 Oscillator-B amount to Direct or Wheel Mod busses 2989 LFO to Direct amount or Wheel Mod busses 2990 2991 Dest: 2992 2993 Oscillator-A frequency from Direct or Wheel Mod busses 2994 Oscillator-A PWM from Direct or Wheel Mod busses 2995 Oscillator-B frequency from Direct or Wheel Mod busses 2996 Oscillator-B PWM from Direct or Wheel Mod busses 2997 Filter Cutoff from Direct or Wheel Mod busses 2998 2999Osc-A: 3000 3001 Tune: +/-7 semitones 3002 Freq: 16' to 2' in octave steps 3003 Shape: Ramp or Square 3004 Pulse Width: only when Square is active. 3005 Sync: synchronise to Osc-B 3006 3007Osc-B: 3008 3009 Tune: +/-7 semitones 3010 Freq: 16' to 2' in octave steps 3011 Fine: +/- 7 semitones 3012 Shape: Ramp/Triangle/Square 3013 Pulse Width: only when Square is active. 3014 LFO: Lowers frequency by 'several' octaves. 3015 KBD: enable/disable keyboard tracking. 3016 3017Mixer: 3018 3019 Gain for Osc-A, Osc-B, Noise 3020 3021Filter: 3022 3023 Cutoff: cuttof frequency 3024 Res: Resonance/Q/Emphasis 3025 Env: amount of modulation affecting to cutoff. 3026 KBD: amount of keyboard trackingn to cutoff 3027 3028Envelopes: One each for PolyMod (filter) and amplifier. 3029 3030 Attack 3031 Decay 3032 Sustain 3033 Release 3034 3035Sequencer: 3036 3037 On/Off 3038 Record Play 3039 Rate configured from LFO 3040 3041Arpeggiator: 3042 3043 Up/Off/UpDown 3044 Rate configured from LFO 3045 3046Glide: 3047 3048 Amount of portamento 3049 Auto/Normal - first key will/not glide. 3050 3051Global: 3052 3053 Master Tune 3054 Master Volume 3055 3056 3057Memories are loaded by selecting the 'Bank' button and typing in a two digit 3058bank number followed by load. Once the bank has been selected then 8 memories 3059from the bank can be loaded by pressing another memory select and pressing 3060load. The display will show free memories (FRE) or programmed (PRG). 3061There is an additional Up/Down which scan for the next program and a 'Find' 3062key which will scan up to the next unused memory location. 3063 3064The original supported two sequences, Seq1 and Seq2, but these have not been 3065implemented. Instead the emulator will save a sequence with each memory location 3066which is a bit more flexible if not totally in the spirit of the original. 3067 3068The Envelope amount for the filter is actually 'Mod Amount'. To get the filter 3069envelope to drive the filter it must be routed to the filter via a mod bus. This 3070may differ from the original. 3071Arpeggiator range is two octaves. 3072The Mode options may not be correctly implemented due to the differences in 3073the original being monophonic and the emulator being polyphonic. The Retrig is 3074actually 'rezero' since we have separate voices. Drone is a Sustain key that 3075emulates a sustain pedal. 3076Osc-B cannot modulate itself in polyphonic mode (well, it could, it's just that 3077it has not been coded that way). 3078The filter envelope is configured to ignore velocity. 3079 3080The default filters are quite expensive. The -lwf option will select the less 3081computationally expensive lightweight Chamberlain filters which have a colder 3082response but require zonks fewer CPU cycles. 3083 3084 3085 3086 3087 Moog Voyager (Bristol "Explorer") 3088 --------------------------------- 3089 3090This was Robert Moog's last synth, similar in build to the Mini but created 3091over a quarter of a century later and having far, far more flexibility. It 3092was still monophonic, a flashback to a legendary synth but also a bit like 3093Bjorn Borg taking his wooden tennis racket back to Wimbledon long after having 3094retired and carbon fibre having come to pass. I have no idea who uses it and 3095Bjorn also crashed out in the first round. The modulation routing is exceptional 3096if not exactly clear. 3097 3098The Voyager, or Bristol Explorer, is definitely a child of the Mini. It has 3099the same fold up control panel, three and half octave keyboard and very much 3100that same look and feel. It follows the same rough design of three oscillators 3101mixed with noise into a filter with envelopes for the filter and amplifier. 3102In contrast there is an extra 4th oscillator, a dedicated LFO bus also Osc-3 3103can still function as a second LFO here. The waveforms are continuously 3104selected, changing gradually to each form: bristol uses a form of morphing 3105get get similar results. The envelopes are 4 stage rather than the 3 stage 3106Mini, and the effects routing bears no comparison at all, being far more 3107flexible here. 3108 3109Just because its funny to know, Robert Moog once stated that the most difficult 3110part of building and releasing the Voyager was giving it the title 'Moog'. He 3111had sold his company in the seventies and had to buy back the right to use his 3112own name to release this synthesiser as a Moog, knowing that without that title 3113it probably would not sell quite as well as it didn't. 3114 3115Control: 3116 3117 LFO: 3118 Frequency 3119 Sync: LFO restarted with each keypress. 3120 3121 Fine tune +/- one note 3122 Glide 0 to 30 seconds. 3123 3124Modulation Busses: 3125 3126 Two busses are implemented. Both have similar capabilities but one is 3127 controlled by the mod wheel and the other is constantly on. Each bus has 3128 a selection of sources, shaping, destination selection and amount. 3129 3130 Wheel Modulation: Depth is controller by mod wheel. 3131 3132 Source: Triwave/Ramp/Sample&Hold/Osc-3/External 3133 Shape: Off/Key control/Envelope/On 3134 Dest: All Osc Frequency/Osc-2/Osc-3/Filter/FilterSpace/Waveform (*) 3135 Amount: 0 to 1. 3136 3137 Constant Modulation: Can use Osc-3 as second LFO to fatten sound. 3138 3139 Source: Triwave/Ramp/Sample&Hold/Osc-3/External 3140 Shape: Off/Key control/Envelope/On 3141 Dest: All Osc Frequency/Osc-2/Osc-3/Filter/FilterSpace/Waveform (*) 3142 Amount: 0 to 1. 3143 3144 * Destination of filter is the cutoff frequency. Filter space is the 3145 difference in cutoff of the two layered filters. Waveform destination 3146 affects the continuously variable oscillator waveforms and allows for 3147 Pulse Width Modulation type effects with considerably more power since 3148 it can affect ramp to triangle for example, not just pulse width. 3149 3150Oscillators: 3151 3152 Oscillator 1: 3153 Octave: 32' to 1' in octave steps 3154 Waveform: Continuous between Triangle/Ramp/Square/Pulse 3155 3156 Oscillator 2: 3157 Tune: Continuous up/down 7 semitones. 3158 Octave: 32' to 1' in octave steps 3159 Waveform: Continuous between Triangle/Ramp/Square/Pulse 3160 3161 Oscillator 3: 3162 Tune: Continuous up/down 7 semitones. 3163 Octave: 32' to 1' in octave steps 3164 Waveform: Continuous between Triangle/Ramp/Square/Pulse 3165 3166 Sync: Synchronise Osc-2 to Osc-1 3167 FM: Osc-3 frequency modulates Osc-1 3168 KBD: Keyboard tracking Osc-3 3169 Freq: Osc-3 as second LFO 3170 3171Mixer: 3172 3173 Gain levels for each source: Osc-1/2/3, noise and external input. 3174 3175Filters: 3176 3177 There are two filters with different configuration modes: 3178 3179 1. Two parallel resonant lowpass filters. 3180 2. Serialised HPF and resonant LPF 3181 3182 Cutoff: Frequency of cutoff 3183 Space: Distance between the cutoff of the two filters. 3184 Resonance: emphasis/Q. 3185 KBD tracking amount 3186 Mode: Select between the two operating modes. 3187 3188Envelopes: 3189 3190 Attack 3191 Decay 3192 Sustain 3193 Release 3194 3195 Amount to filter (positive and negative control) 3196 3197 Velocity sensitivity of amplifier envelope. 3198 3199Master: 3200 3201 Volume 3202 LFO: Single LFO or one per voice (polyphonic operation). 3203 Glide: On/Off portamento 3204 Release: On/Off envelope release. 3205 3206The Explorer has a control wheel and a control pad. The central section has 3207the memory section plus a panel that can modify any of the synth parameters as 3208a real time control. Press the first mouse key here and move the mouse around 3209to adjust the controls. Default values are LFO frequency and filter cutoff 3210but values can be changed with the 'panel' button. This is done by selecting 3211'panel' rather than 'midi', and then using the up/down keys to select parameter 3212that will be affected by the x and y motion of the mouse. At the moment the 3213mod routing from the pad controller is not saved to the memories, and it will 3214remain so since the pad controller is not exactly omnipresent on MIDI master 3215keyboards - the capabilities was put into the GIU to be 'exact' to the design. 3216 3217This synth is amazingly flexible and difficult to advise on its best use. Try 3218starting by mixing just oscillator 1 through to the filter, working on mod 3219and filter options to enrich the sound, playing with the oscillator switches 3220for different effects and then slowly mix in oscillator 2 and 3 as desired. 3221 3222Memories are available via two grey up/down selector buttons, or a three digit 3223number can be entered. There are two rows of black buttons where the top row 3224is 0 to 4 and the second is 5 to 9. When a memory is selected the LCD display 3225will show whether it is is free (FRE) or programmed already (PRG). 3226 3227 3228 3229 3230 Moog Sonic-6 3231 ------------ 3232 3233This original design was made by an engineer who had previously worked with 3234Moog on the big modular systems, Gene Zumchek. He tried to get Moog Inc to 3235develop a small standalone unit rather than the behemoths however he could 3236not get heard. After leaving he built a synth eventually called a Sonic-5 that 3237did fit the bill but sales volumes were rather small. He had tied up with a 3238business manager who worked out that the volume was largely due to the name 3239not being known, muSonics. 3240This was quickly overcome by accident. Moog managed to run his company into 3241rather large debt and the company folded. Bill Waytena, working with Zumcheck, 3242gathered together the funding needed to buy the remains of the failed company 3243and hence Moog Inc was labled on the rebadged Sonic-6. Zumcheck was eventually 3244forced to leave this company (or agreed to) as he could not work with Moog. 3245After a few modifications Bob Moog actually used this unit quite widely for 3246lecturing on electronic music. For demonstrative purposes it is far more 3247flexible than any of Moog's own non-modular designs and it was housed in a 3248transport case rather than needing a shipping crate as the modular systems 3249required. 3250 3251The emulation features are given below, but first a few of the differences to 3252the original 3253 3254 Added a mod wheel that can drive GenX/Y. 3255 PWM is implemented on the oscillator B 3256 Installed an ADSR rather than AR, selectable. 3257 No alternative scalings - use scala file support 3258 Not duo or dia phonic. Primarily poly with separated glide. 3259 3260The original was duophonic, kind of. It had a keyboard with high note and low 3261note precedence and the two oscillators could be driven from different notes. 3262Its not really duophony and was reportedly not nice to play but it added some 3263flexibility to the instrument. This features was dropped largley because it 3264is ugly to emulate in a polyphonic environment but the code still has glide 3265only on Osc-B. It has the two LFO that can be mixed, or at full throw of the 3266GenXY mixer they will link X->A and Y->B giving some interesting routing, two 3267osc each with their own LFO driving the LFO from the mod wheel or shaping it 3268with the ADSR. Playing around should give access to X driving Osc-A, then 3269Osc-A and GenY driving Osc-B with Mod and shaping for some investigation of 3270FM synthesis. The gruesome direct output mixer is still there, having the osc 3271and ring-mod bypass the filter and amplifier completely (or can be mixed back 3272into the 'actuated' signal). 3273 3274There is currently no likely use for an external signal even though the 3275graphics are there. 3276 3277The original envelope was AR or ASR. The emulator has a single ADSR and a 3278control switch to select AR (actually AD), ASR, ADSD (MiniMoog envelope) or 3279ADSR. 3280 3281Generator-Y has a S/H function on the noise source for a random signal which 3282replaced the square wave. Generator-X still has a square wave. 3283 3284Modulators: 3285 3286 Two LFO, X and Y: 3287 3288 Gen X: 3289 Tri/Ramp/Saw/Square 3290 Tuning 3291 Shaping from Envelope or Modwheel 3292 3293 Gen Y: 3294 Tri/Ramp/Saw/Rand 3295 Tuning 3296 Shaping from Envelope or Modwheel 3297 3298 Master LFO frequency 3299 3300 GenXY mixer 3301 3302 Two Oscillators, A and B 3303 3304 Gen A: 3305 Tri/Ramp/Pulse 3306 PulseWidth 3307 Tuning 3308 Transpose 16', 8', 4' (*) 3309 3310 Mods: 3311 3312 Envelope 3313 GenXY(or X) 3314 Low frequency, High Frequency (drone), KBD Tracking 3315 3316 Gen B: 3317 Tri/Ramp/Pulse 3318 PulseWidth 3319 Tuning 3320 Transpose 16' 8', 4' 3321 3322 Mods: 3323 3324 Osc-B 3325 GenXY(or Y) 3326 PWM 3327 3328 GenAB mix 3329 3330 Ring Mod: 3331 3332 Osc-B/Ext 3333 GenXY/Osc-A 3334 3335 Noise 3336 3337 Pink/White 3338 3339 Mixer 3340 3341 GenAB 3342 RingMod 3343 External 3344 Noise 3345 3346 Filter (**) 3347 3348 Cutoff 3349 Emphasis 3350 3351 Mods: 3352 3353 ADSR 3354 Keyboard tracking 3355 GenXY 3356 3357 Envelope: 3358 3359 AR/ASR/ADSD/ADSR 3360 Velociy on/off 3361 3362 Trigger: 3363 3364 GenX 3365 GenY 3366 Kbd (rezero only) 3367 3368 Bypass (key gated audio) 3369 3370 Direct Output Mixer 3371 3372 Osc-A 3373 Osc-B 3374 RingMod 3375 3376 3377The keyboard has controls for 3378 3379 Glide (Osc-B only) 3380 Master Volume 3381 PitchWheel 3382 ModWheel (gain modifier on LFO) 3383 3384 Global Tuning 3385 3386 MultiLFO X and Y 3387 3388* The oscillator range was +/-2 octave switch and a +/-1 octave pot. This 3389emulator has +/-1 octave switch and +/-7 note pot. That may change in a future 3390release to be more like the original, probably having a multiway 5 stage octave 3391selector. 3392 3393** The filter will self oscillate at full emphasis however this is less 3394prominent at lower frequencies (much like the Moog ladder filter). The filter 3395is also 'not quite' in tune when played as an oscillator, this will also change 3396in a future release. 3397 3398There may be a reverb on the emulator. Or there may not be, that depends on 3399release. The PitchWheel is not saved in the memories, the unit is tuned on 3400startup and this will maintain tuning to other instruments. The MultiLFO allow 3401you to configure single LFO per emulation or one per voice, independently. 3402Having polyphony means you can have the extra richness of independent LFO per 3403voice however that does not work well if they are used as triggers, for example, 3404you end up with a very noisy result. With single triggers for all voices the 3405result is a lot more predictable. 3406 3407The Sonic-6 as often described as having bad tuning, that probably depends on 3408model since different oscillators were used at times. Also, different units 3409had different filters (Zumchek used a ladder of diodes to overcome the Moog 3410ladder of transister patent). The original was often described as only being 3411useful for sound effects. Personally I don't think that was true however the 3412design is extremely flexible and the mods are applied with high gains so to 3413get subtle sounds they only have to be applied lightly. Also, this critique 3414was in comparison to the Mini which was not great for sound effects since it, 3415in contrast, had very little in the way of modifiers. 3416 3417The actual mod routing here is very rich. The two LFO can be mixed to provide 3418for more complex waves and have independent signal gain from the ADSR. To go 3419a step further it is possible to take the two mixed LFO into Osc-A, configure 3420that as an LFO and feed it into Osc-B for some very complex mod signals. That 3421way you can get a frequency modulated LFO which is not possible from X or Y. As 3422stated, if these are applied heavily you will get ray guns and car alarms but 3423in small amounts it is possible to just shape sounds. Most of the mod controls 3424have been made into power functions to give more control at small values. 3425 3426The memory panel gives access to 72 banks of 8 memories each. Press the Bank 3427button and two digits for the bank, then just select the memory and press Load. 3428You can get the single digit banks by selecting Bank->number->Bank. There is 3429a save button which should require a double click but does not yet (0.30.0), 3430a pair of buttons for searching up and down the available memories and a button 3431called 'Find' which will select the next available free memory. 3432 3433Midi options include channel, channel down and, er, thats it. 3434 3435 3436 3437 3438 CRUMAR TRILOGY 3439 -------------- 3440 3441This text is primarily that of the Stratus since the two synths were very 3442similar. This is the bigger brother having all the same features with the added 3443string section. There were some minor differences in the synth circuits for 3444switchable or mixable waveforms. 3445 3446This unit is a hybrid synth/organ/string combo, an early polyphonic using an 3447organ divider circuit rather than independent VCO and having a set of filters 3448and envelope for the synth sounds, most manufacturers came out with similar 3449designs. The organ section was generally regarded as pretty bad here, there 3450were just five controls, four used for the volume of 16, 8, 4 and 2 foot 3451harmonics and a fifth for overall organ volume. The synth section had 6 voices 3452and some quite neat little features for a glide circuitry and legato playing 3453modes. The string section could mix 3 waveforms with vibrato on some so when 3454mixed with the straight waveform would produce phasing. 3455 3456The emulator consists of two totally separate layers, one emulating the organ 3457circuitry and another the synth. The organ has maximum available polyphony as 3458the algorithm is quite lightweight even though diverse liberties have been 3459taken to beef up the sound. The synth section is limited to 6 voices unless 3460otherwise specified at run time. The organ circuitry is used to generate the 3461string section. 3462 3463The legato playing modes affects three sections, the LFO modulation, VCO 3464selection and glide: 3465 3466LFO: this mod has a basic envelope to control the gain of the LFO using delay, 3467slope and gain. In 'multi' mode the envelope is triggered for every note that 3468is played and in the emulator this is actually a separate LFO per voice, a bit 3469fatter than the original. In 'Mono' mode there is only one LFO that all voices 3470will share and the envelope is triggered in Legato style, ie, only once for 3471a sequence of notes - all have to be released for the envelope to recover. 3472 3473VCO: The original allowed for wavaeform selection to alternate between notes, 3474something that is rather ugly to do with the bristol architecture. This is 3475replaced with a VCO selector where each note will only take the output from 3476one of the two avalable oscillators and gives the ntoes a little more 3477separation. The legato mode works whereby the oscillator selection is only 3478made for the first note in a sequence to give a little more sound consistency. 3479 3480Glide: This is probably the coolest feature of the synth. Since it used an 3481organ divider circuit it was not possible to actually glide from one note to 3482another - there are really only two oscillators in the synth section, not two 3483per voice. In contrast the glide section could glide up or down from a selected 3484amount to the real frequency. Selected from down with suitable values would 3485give a nice 'blue note' effect for example. In Legato mode this is done only 3486for the first keypress rather than all of the since the effect can be a bit 3487over the top if applied to each keystroke in a sequence. At the same time it 3488was possible to Sync the two oscillators, so having only one of them glide 3489and be in sync then without legato this gave a big phasing entrance to each 3490note, a very interesting effect. The Glide has 4 modes: 3491 3492 A. Both oscillators glide up to the target frequency 3493 B. Only oscillator-2 glides up to the target frequency 3494 C. Only oscillator-2 glides down to the target frequency 3495 D. Both oscillators glide down to the target frequency 3496 3497These glide options with different sync and legato lead to some very unique 3498sounds and are emulated here with only minor differences. 3499 3500The features, then notes on the differences to the original: 3501 3502 A. Organ Section 3503 3504 16, 8, 4 and 2 foot harmonic strengths. 3505 Volume. 3506 3507 B. Synth Section 3508 3509 LFO Modulation 3510 3511 Rate - 0.1 to 50Hz approx 3512 Slope - up to 10 seconds 3513 Delay - up to 10 seconds 3514 Gain 3515 3516 Routing selector: VCO, VCF, VCA 3517 Mono/Multi legato mode 3518 Shape - Tri/Ramp/Saw/Square 3519 3520 Oscillator 1 3521 3522 Tuning 3523 Sync 2 to 1 3524 Octave selector 3525 3526 Oscillator 2 3527 3528 Tuning 3529 Octave trill 3530 Octave selector 3531 3532 Waveform Ramp and Square mix 3533 Alternate on/off 3534 Mono/Multi legato mode VCO selection 3535 3536 Glide 3537 3538 Amount up or down from true frequency 3539 Speed of glide 3540 Mono/Multi legato mode 3541 Direction A, B, C, D 3542 3543 Filter 3544 3545 Cutoff frequency 3546 Resonance 3547 Envelope tracking -ve to +ve 3548 Pedal tracking on/off 3549 3550 Envelope 3551 3552 Attack 3553 Decay 3554 Sustain 3555 Release 3556 3557 Gain 3558 3559 C. String Section 3560 3561 16' 8' mix 3562 Subharmonic gain 3563 Attack 3564 Release 3565 3566 Volume 3567 3568Diverse liberties were taken with the reproduction, these are manageable from 3569the options panel by selecting the button next to the keyboard. This opens up 3570a graphic of a PCB, mostly done for humorous effect as it not in the least bit 3571representative of the actual hardware. Here there are a number of surface 3572mounted controllers. These are as below but may change by release: 3573 3574 P1 Master volume 3575 3576 P2 Organ pan 3577 P3 Organ waveform distorts 3578 P4 Organ spacialisation 3579 P5 Organ mod level 3580 J1 Organ key grooming 3581 P6 Organ tuning (currently inactive *) 3582 3583 P7 Synth pan 3584 P8 Synth tuning 3585 P9 Synth osc1 harmonics 3586 P10 Synth osc2 harmonics 3587 J2 Synth velocity sensitivity 3588 J3 Synth filter type 3589 P11 Synth filter tracking 3590 3591 P12 String pan 3592 P13 String harmonics 3593 P14 String spacialisation 3594 P15 String mod level 3595 P16 String waveform distorts 3596 3597*: To make the organ tunable the keymap file has to be removed. 3598 3599Master (P1) volume affects both layers simultaneously and each layer can be 3600panned (P2/P7) and tuned (P8) separately to give phasing and spacialisation. 3601The synth layer has the default frequency map of equal temperament however the 3602organ section uses a 2MHz divider frequency map that is a few cents out for 3603each key. The Trilogy actually has this map for both layers and that can easily 3604be done with the emulator, details on request. 3605 3606It is currently not possible to retune the organ divider circuit, it has a 3607private microtonal mapping to emulate the few percent anomalies of the divider 3608circuit and the frequencies are predefined. The pot is still visible in P6 and 3609can be activated by removing the related microtonal mapping file, details from 3610the author on request. 3611 3612Diverse liberties were taken with the Organ section since the original only 3613produced 4 pure (infinite bandwidth) square waves that were mixed together, 3614an overly weak result. The emulator adds a waveform distort (P3), an notched 3615control that produces a pure sine wave at centre point. Going down it will 3616generate gradually increasing 3rd and 5th harmonics to give it a squarey wave 3617with a distinct hammond tone. The distortion actually came from the B3 emulator 3618which models the distort on the shape of the hammond tonewheels themselves. 3619Going up from centre point will produce gradually sharper sawtooth waves using 3620a different phase distortion. 3621 3622Organ spacialisation (P4) will separate out the 4 harmonics to give them 3623slightly different left and right positions to fatten out the sound. This works 3624in conjunction with the mod level (P5) where one of the stereo components of 3625each wave is modified by the LFO to give phasing changes up to vibrato. 3626 3627The organ key grooming (J1) will either give a groomed wave to remove any 3628audible clicks from the key on and off events or when selected will produce 3629something akin to a percussive ping for the start of the note. 3630 3631The result for the organ section is that it can produce some quite nice sounds 3632reminiscent of the farfisa range to not quite hammond, either way far more 3633useful than the flat, honking square waves. The original sound can be made by 3634waveform to a quarter turn or less, spacialisation and mod to zero, key 3635grooming off. 3636 3637The synth has 5 modifications at the first release. The oscillator harmonics 3638can be fattened at the top or bottom using P9 and P10, one control for each 3639oscillator, low is more bass, high is more treble. Some of the additional 3640harmonics will be automatically detuned a little to fatten out the sound as a 3641function of the -detune parameter defaulting to 100. 3642 3643The envelope can have its velocity sensitively to the filter enabled or disabled 3644(J2) and the filter type can be a light weight filter for a thinner sound but at 3645far lower CPU load (J3). 3646 3647The filter keyboard tracking is configurable (P11), this was outside of the spec 3648of the Trilogy however it was implemented here to correct the keyboard tracking 3649of the filter for all the emulations and the filter should now be playable. 3650The envelope touch will affect this depending on J2 since velocity affects the 3651cut off frequency and that is noticeable when playing the filter. This jumper 3652is there so that the envelope does not adversely affect tuning but can still be 3653used to have the filter open up with velocity if desired. 3654 3655The mod application is different from the original. It had a three way selector 3656for routing the LFO to either VCO, VCA or VCF but only a single route. This 3657emulation uses a continuous notched control where full off is VCO only, notch 3658is VCF only and full on is VCA however the intermidiate positions will route 3659proportional amounts to two components. 3660 3661The LFO has more options (Ramp and Saw) than the original (Tri and Square). 3662 3663The extra options are saved with each memory however they are only loaded at 3664initialisation and when the 'Load' button is double-clicked. This allows you to 3665have them as global settings or per memory as desired. The MemUp and MemDown 3666will not load the options, only the main settings. 3667 3668VCO mod routing is a little bit arbitrary in this first release however I could 3669not find details of the actual implementation. The VCO mod routing only goes 3670to Osc-1 which also takes mod from the joystick downward motion. Mod routing 3671to Osc-2 only happens if 'trill' is selected. This seemed to give the most 3672flexibility, directing the LFO to VCF/VCA and controlling vibrato from the 3673stick, then having Osc-2 separate so that it can be modified and sync'ed to 3674give some interesting phasing. 3675 3676As of the first release there are possibly some issues with the oscillator 3677Sync selector, it is perhaps a bit noisy with a high content of square wave. 3678Also, there are a couple of minor improvements that could be made to the 3679legato features but they will be done in a future release. They regard how 3680the glide is applied to the first or all in a sequence of notes. 3681 3682The joystick does not always pick up correctly however it is largely for 3683presentation, doing actual work you would use a real joystick or just use the 3684modwheel (the stick generates and tracks continuous controller 1 - mod). The 3685modwheel tracking is also a bit odd but reflects the original architecture - 3686at midpoint on the wheel there is no net modulation, going down affects VCO 3687in increasing amounts and going up from mid affect the VCF. The control feels 3688like it should be notched however generally that is not the case with mod 3689wheels. 3690 3691A few notes are required on oscillator sync since by default it will seem to 3692be quite noisy. The original could only product a single waveform at a single 3693frequency at any one time. Several emulators, including this one, use a bitone 3694oscillator which generates complex waveforms. The Bristol Bitone can generate 3695up to 4 waveforms simultaneously at different levels for 5 different harmonics 3696and the consequent output is very rich, the waves can be slightly detuned, 3697the pulse output can be PW modulated. As with all the bristol oscillators that 3698support sync, the sync pulse is extracted as a postive leading zero crossing. 3699Unfortunately if the complex bitone output is used as input to sync another 3700oscillator then the result is far too many zero crossings to extract a good 3701sync. For the time being you will have to simplify the sync source to get a 3702good synchronised output which itself may be complex wave. A future release 3703will add a sync signal from the bitone which will be a single harmonic at the 3704base frequency and allow both syncing and synchronised waveform outputs to be 3705arbitrary. For the Trilogy this simplification of the sync waveform is done 3706automatically by the Sync switch, this means the synchronised output sounds 3707correct but the overall waveform may be simpler. 3708 3709 3710 3711 3712 CRUMAR STRATUS 3713 -------------- 3714 3715This unit is a hybrid synth/organ combo, an early polyphonic synth using an 3716organ divider circuit rather than independent VCO and having a set of filters 3717and envelope for the synth sounds, most manufacturers came out with similar 3718designs. The organ section was generally regarded as pretty bad here, there 3719were just five controls, four used for the volume of 16, 8, 4 and 2 foot 3720harmonics and a fifth for overall organ volume. The synth section had 6 voices 3721and some quite neat little features for a glide circuitry and legato playing 3722modes. 3723 3724The emulator consists of two totally separate layers, one emulating the organ 3725circuitry and another the synth. The organ has maximum available polyphony as 3726the algorithm is quite lightweight even though diverse liberties have been 3727taken to beef up the sound. The synth section is limited to 6 voices unless 3728otherwise specified at run time. 3729 3730The legato playing modes affects three sections, the LFO modulation, VCO 3731selection and glide: 3732 3733LFO: this mod has a basic envelope to control the gain of the LFO using delay, 3734slope and gain. In 'multi' mode the envelope is triggered for every note that 3735is played and in the emulator this is actually a separate LFO per voice, a bit 3736fatter than the original. In 'Mono' mode there is only one LFO that all voices 3737will share and the envelope is triggered in Legato style, ie, only once for 3738a sequence of notes - all have to be released for the envelope to recover. 3739 3740VCO: The original allowed for wavaeform selection to alternate between notes, 3741something that is rather ugly to do with the bristol architecture. This is 3742replaced with a VCO selector where each note will only take the output from 3743one of the two avalable oscillators and gives the ntoes a little more 3744separation. The legato mode works whereby the oscillator selection is only 3745made for the first note in a sequence to give a little more sound consistency. 3746 3747Glide: This is probably the coolest feature of the synth. Since it used an 3748organ divider circuit it was not possible to actually glide from one note to 3749another - there are really only two oscillators in the synth section, not two 3750per voice. In contrast the glide section could glide up or down from a selected 3751amount to the real frequency. Selected from down with suitable values would 3752give a nice 'blue note' effect for example. In Legato mode this is done only 3753for the first keypress rather than all of the since the effect can be a bit 3754over the top if applied to each keystroke in a sequence. At the same time it 3755was possible to Sync the two oscillators, so having only one of them glide 3756and be in sync then without legato this gave a big phasing entrance to each 3757note, a very interesting effect. The Glide has 4 modes: 3758 3759 A. Both oscillators glide up to the target frequency 3760 B. Only oscillator-2 glides up to the target frequency 3761 C. Only oscillator-2 glides down to the target frequency 3762 D. Both oscillators glide down to the target frequency 3763 3764These glide options with different sync and legato lead to some very unique 3765sounds and are emulated here with only minor differences. 3766 3767The features, then notes on the differences to the original: 3768 3769 A. Organ Section 3770 3771 16, 8, 4 and 2 foot harmonic strengths. 3772 Volume. 3773 3774 B. Synth Section 3775 3776 LFO Modulation 3777 3778 Rate - 0.1 to 50Hz approx 3779 Slope - up to 10 seconds 3780 Delay - up to 10 seconds 3781 Gain 3782 3783 Routing selector: VCO, VCF, VCA 3784 Mono/Multi legato mode 3785 Shape - Tri/Ramp/Saw/Square 3786 3787 Oscillator 1 3788 3789 Tuning 3790 Sync 2 to 1 3791 Octave selector 3792 3793 Oscillator 2 3794 3795 Tuning 3796 Octave trill 3797 Octave selector 3798 3799 Waveform Ramp and Square mix 3800 Alternate on/off 3801 Mono/Multi legato mode VCO selection 3802 3803 Glide 3804 3805 Amount up or down from true frequency 3806 Speed of glide 3807 Mono/Multi legato mode 3808 Direction A, B, C, D 3809 3810 Filter 3811 3812 Cutoff frequency 3813 Resonance 3814 Envelope tracking -ve to +ve 3815 Pedal tracking on/off 3816 3817 Envelope 3818 3819 Attack 3820 Decay 3821 Sustain 3822 Release 3823 3824 Gain 3825 3826Diverse liberties were taken with the reproduction, these are manageable from 3827the options panel by selecting the button next to the keyboard. This opens up 3828a graphic of a PCB, mostly done for humorous effect as it not in the least bit 3829representative of the actual hardware. Here there are a number of surface 3830mounted controllers. These are as below but may change by release: 3831 3832 P1 Master volume 3833 3834 P2 Organ pan 3835 P3 Organ waveform distorts 3836 P4 Organ spacialisation 3837 P5 Organ mod level 3838 J1 Organ key grooming 3839 P6 Organ tuning (currently inactive *) 3840 3841 P7 Synth pan 3842 P8 Synth tuning 3843 P9 Synth osc1 harmonics 3844 P10 Synth osc2 harmonics 3845 J2 Synth velocity sensitivity 3846 J3 Synth filter type 3847 P11 Synth filter tracking 3848 3849*: To make the organ tunable the keymap file has to be removed. 3850 3851Master (P1) volume affects both layers simultaneously and each layer can be 3852panned (P2/P7) and tuned (P8) separately to give phasing and spacialisation. 3853The synth layer has the default frequency map of equal temperament however the 3854organ section uses a 2MHz divider frequency map that is a few cents out for 3855each key. The Stratus actually has this map for both layers and that can easily 3856be done with the emulator, details on request. 3857 3858It is currently not possible to retune the organ divider circuit, it has a 3859private microtonal mapping to emulate the few percent anomalies of the divider 3860circuit and the frequencies are predefined. The pot is still visible in P6 and 3861can be activated by removing the related microtonal mapping file, details from 3862the author on request. 3863 3864Diverse liberties were taken with the Organ section since the original only 3865produced 4 pure (infinite bandwidth) square waves that were mixed together, 3866an overly weak result. The emulator adds a waveform distort (P3), an notched 3867control that produces a pure sine wave at centre point. Going down it will 3868generate gradually increasing 3rd and 5th harmonics to give it a squarey wave 3869with a distinct hammond tone. The distortion actually came from the B3 emulator 3870which models the distort on the shape of the hammond tonewheels themselves. 3871Going up from centre point will produce gradually sharper sawtooth waves using 3872a different phase distortion. 3873 3874Organ spacialisation (P4) will separate out the 4 harmonics to give them 3875slightly different left and right positions to fatten out the sound. This works 3876in conjunction with the mod level (P5) where one of the stereo components of 3877each wave is modified by the LFO to give phasing changes up to vibrato. 3878 3879The organ key grooming (J1) will either give a groomed wave to remove any 3880audible clicks from the key on and off events or when selected will produce 3881something akin to a percussive ping for the start of the note. 3882 3883The result for the organ section is that it can produce some quite nice sounds 3884reminiscent of the farfisa range to not quite hammond, either way far more 3885useful than the flat, honking square waves. The original sound can be made by 3886waveform to a quarter turn or less, spacialisation and mod to zero, key 3887grooming off. 3888 3889The synth has 5 modifications at the first release. The oscillator harmonics 3890can be fattened at the top or bottom using P9 and P10, one control for each 3891oscillator, low is more bass, high is more treble. Some of the additional 3892harmonics will be automatically detuned a little to fatten out the sound as a 3893function of the -detune parameter defaulting to 100. 3894 3895The envelope can have its velocity sensitively to the filter enabled or disabled 3896(J2) and the filter type can be a light weight filter for a thinner sound but at 3897far lower CPU load (J3). 3898 3899The filter keyboard tracking is configurable (P11), this was outside of the spec 3900of the Stratus however it was implemented here to correct the keyboard tracking 3901of the filter for all the emulations and the filter should now be playable. 3902The envelope touch will affect this depending on J2 since velocity affects the 3903cut off frequency and that is noticeable when playing the filter. This jumper 3904is there so that the envelope does not adversely affect tuning but can still be 3905used to have the filter open up with velocity if desired. 3906 3907The mod application is different from the original. It had a three way selector 3908for routing the LFO to either VCO, VCA or VCF but only a single route. This 3909emulation uses a continuous notched control where full off is VCO only, notch 3910is VCF only and full on is VCA however the intermidiate positions will route 3911proportional amounts to two components. 3912 3913The LFO has more options (Ramp and Saw) than the original (Tri and Square). 3914 3915The extra options are saved with each memory however they are only loaded at 3916initialisation and when the 'Load' button is double-clicked. This allows you to 3917have them as global settings or per memory as desired. The MemUp and MemDown 3918will not load the options, only the main settings. 3919 3920VCO mod routing is a little bit arbitrary in this first release however I could 3921not find details of the actual implementation. The VCO mod routing only goes 3922to Osc-1 which also takes mod from the joystick downward motion. Mod routing 3923to Osc-2 only happens if 'trill' is selected. This seemed to give the most 3924flexibility, directing the LFO to VCF/VCA and controlling vibrato from the 3925stick, then having Osc-2 separate so that it can be modified and sync'ed to 3926give some interesting phasing. 3927 3928As of the first release there are possibly some issues with the oscillator 3929Sync selector, it is perhaps a bit noisy with a high content of square wave. 3930Also, there are a couple of minor improvements that could be made to the 3931legato features but they will be done in a future release. They regard how 3932the glide is applied to the first or all in a sequence of notes. 3933 3934The joystick does not always pick up correctly however it is largely for 3935presentation, doing actual work you would use a real joystick or just use the 3936modwheel (the stick generates and tracks continuous controller 1 - mod). The 3937modwheel tracking is also a bit odd but reflects the original architecture - 3938at midpoint on the wheel there is no net modulation, going down affects VCO 3939in increasing amounts and going up from mid affect the VCF. The control feels 3940like it should be notched however generally that is not the case with mod 3941wheels. 3942 3943A few notes are required on oscillator sync since by default it will seem to 3944be quite noisy. The original could only product a single waveform at a single 3945frequency at any one time. Several emulators, including this one, use a bitone 3946oscillator which generates complex waveforms. The Bristol Bitone can generate 3947up to 4 waveforms simultaneously at different levels for 5 different harmonics 3948and the consequent output is very rich, the waves can be slightly detuned, 3949the pulse output can be PW modulated. As with all the bristol oscillators that 3950support sync, the sync pulse is extracted as a postive leading zero crossing. 3951Unfortunately if the complex bitone output is used as input to sync another 3952oscillator then the result is far too many zero crossings to extract a good 3953sync. For the time being you will have to simplify the sync source to get a 3954good synchronised output which itself may be complex wave. A future release 3955will add a sync signal from the bitone which will be a single harmonic at the 3956base frequency and allow both syncing and synchronised waveform outputs to be 3957arbitrary. For the Stratus this simplification of the sync waveform is done 3958automatically by the Sync switch, this means the synchronised output sounds 3959correct but the overall waveform may be simpler. 3960 3961 3962 3963 3964 KORG POLY 800 3965 ------------- 3966 3967This is a low cost hybrid synth, somewhere between the Korg PolySix and their 3968Mono/Poly in that is polyphonic but only has one filter rather than one per 3969voice that came with the PolySix. It may have also used organ divider circuits 3970rather than individual oscillators - it did not have glide as a feature which 3971would be indicative of a divider circuit. 3972 3973It featured 8 oscillators that could be applied as either 4 voices with dual 3974osc or 8 voices with a single osc. The architecture was verging on the 3975interesting since each oscillator was fead into an individual envelope generator 3976(described below) and then summed into the single filter, the filter having 3977another envelope generator, 9 in total. This lead to cost reduction over having 3978a filter per voice however the single filter leads to breathing, also discussed 3979below. The envelopes were digitally generated by an on-board CPU. 3980 3981The control panel has a volume, global tuning control and a 'Bend' control 3982that governs the depth of the pitch bend from the joystick and the overall 3983amount of DCO modulation applied by the joystick. There is no sequencer in 3984this emulation largely because there are far better options now available than 3985this had but also due to a shortage of onscreen realestate. 3986 3987The Poly, Chord and Hold keys are emulated, hold being a sustain key. The 3988Chord relearn function works follows: 3989 3990 Press the Hold key 3991 Press the Chord key with 2 seconds 3992 Press the notes on the keyboard (*) 3993 Press the Chord key again 3994 3995After that the single chord can be played from a single note as a monophonic 3996instrument. The Chord is saved individually with each memory. 3997* Note that the chord is only saved if (a) it was played from the GUI keyboard 3998or (b) the GUI was linked up to any MIDI device as well as the engine. The 3999reason is that the GUI maintains memories and so if a chord is played on your 4000actual keyboard then both the engine and the GUI needs a copy, the engine to 4001be able to play the notes and the GUI to be able to save them. 4002 4003The keypanel should function very similar to the original. There is a Prog 4004button that selects between Program selection or Parameter selection and an 4005LED should show where the action is. There is the telephone keyboard to enter 4006program or parameters numbers and an up/down selector for parameter value. 4007The Bank/Hold selector also works, it fixes the bank number so programs can 4008be recalled from a single bank with a single button press. The Write function 4009is as per the original - Press Write, then two digits to save a memory. 4010 4011The front panel consists of a data entry panel and a silkscreen of the parameter 4012numbers (this silkscreen is active in the emulation). Fifty parameters are 4013available from the original instrument: 4014 4015 DE 11 DCO1 Octave transposition +2 octaves 4016 DE 12 DCO1 Waveform Square or Ramp 4017 DE 13 DCO1 16' harmonic 4018 DE 14 DCO1 8' harmonic 4019 DE 15 DCO1 4' harmonic 4020 DE 16 DCO1 2' harmonic 4021 DE 17 DCO1 level 4022 4023 DE 18 DCO Double (4 voice) or Single (8 voice) 4024 4025 DE 21 DCO2 Octave transposition +2 octaves 4026 DE 22 DCO2 Waveform Square or Ramp 4027 DE 23 DCO2 16' harmonic 4028 DE 24 DCO2 8' harmonic 4029 DE 25 DCO2 4' harmonic 4030 DE 26 DCO2 2' harmonic 4031 DE 27 DCO2 level 4032 DE 31 DCO2 semitone transpose 4033 DE 32 DCO2 detune 4034 4035 DE 33 Noise level 4036 4037 DE 41 Filter cutoff frequency 4038 DE 42 Filter Resonance 4039 DE 43 Filter Keyboard tracking off/half/full 4040 DE 44 Filter Envelope polarity 4041 DE 45 Filter Envelope amount 4042 DE 46 Filter Envelope retrigger 4043 4044 DE 48 Chorus On/Off 4045 4046 DE 51 Env-1 DCO1 Attack 4047 DE 52 Env-1 DCO1 Decay 4048 DE 53 Env-1 DCO1 Breakpoint 4049 DE 54 Env-1 DCO1 Slope 4050 DE 55 Env-1 DCO1 Sustain 4051 DE 56 Env-1 DCO1 Release 4052 4053 DE 61 Env-2 DCO2 Attack 4054 DE 62 Env-2 DCO2 Decay 4055 DE 63 Env-2 DCO2 Breakpoint 4056 DE 64 Env-2 DCO2 Slope 4057 DE 65 Env-2 DCO2 Sustain 4058 DE 66 Env-2 DCO2 Release 4059 4060 DE 71 Env-3 Filter Attack 4061 DE 72 Env-3 Filter Decay 4062 DE 73 Env-3 Filter Breakpoint 4063 DE 74 Env-3 Filter Slope 4064 DE 75 Env-3 Filter Sustain 4065 DE 76 Env-3 Filter Release 4066 4067 DE 81 Mod LFO Frequency 4068 DE 82 Mod Delay 4069 DE 83 Mod DCO 4070 DE 84 Mod VCF 4071 4072 DE 86 Midi channel 4073 DE 87 Midi program change enable 4074 DE 88 Midi OMNI 4075 4076Of these 25 pararmeters, the emulation has changed 88 to be OMNI mode rather 4077than the original sequence clock as internal or external. This is because the 4078sequencer function was dropped as explained above. 4079 4080Additional to the original many of the controls which are depicted as on/off 4081are actually continuous. For example, the waveform appears to be either square 4082or ramp. The emulator allows you to use the up/down Value keys to reproduce 4083this however if you use the potentiometer then you can gradually move from one 4084wave to the next. The different harmonics are also not on/off, you can mix 4085each of them together with different amounts and if you configure a mixture 4086of waveforms and a bit of detune the sound should widen due to addition of a 4087bit of phasing within the actual oscillator. 4088 4089The envelope generators are not typical ADSR. There is an initial attack from 4090zero to max gain then decay to a 'Breakpoint'. When this has been reached then 4091the 'Slope' parameter will take the signal to the Sustain level, then finally 4092the release rate. The extra step of breakpoint and slope give plenty of extra 4093flexibility to try and adjust for the loss of a filter per voice and the 4094emulation has a linear step which should be the same as the original. The 4095ninth envelope is applied to the single filter and also as the envelope for 4096the noise signal level. 4097 4098The single filter always responded to the highest note on the keyboard. This 4099gives a weaker overall sound and if playing with two hands then there is a 4100noticible effect with keytracking - left hand held chords will cause filter 4101breathing as the right hand plays solos and the keyboard tracking changes 4102from high to low octaves. Note that the emulator will implement a single 4103filter if you select DE 46 filter envelope retrigger to be single trigger, it 4104will be played legato style. If multiple triggers are selected then the 4105emulator will produce a filter and envelope for each voice. 4106 4107Bristol adds a number of extra parameters to the emulator that are not 4108available from the mouse on the silkscreen and were not a part of the design 4109of the poly800. You have to select Prog such that the LED is lit next to the 4110Param display, then select the two digit parameter from the telephone keyboard: 4111 4112 DE 28 DCO Sync 2 to 1 4113 DE 34 DCO-1 PW 4114 DE 35 DCO-1 PWM 4115 DE 36 DCO-2 PW 4116 DE 37 DCO-2 PWM 4117 DE 38 DCO temperature sensitivity 4118 DE 67 DCO Glide 4119 4120 DE 85 Mod - Uni/Multi per voice or globally 4121 4122 DE 57 Envelope Touch response 4123 4124 DE 47 Chorus Parameter 0 4125 DE 58 Chorus Parameter 1 4126 DE 68 Chorus Parameter 2 4127 DE 78 Chorus Parameter 3 4128 4129If DataEntry 28 is selected for oscillator sync then LFO MOD to DCO-1 is no 4130longer applied, it only goes to DCO-2. This allows for the interesting sync 4131modulated slow vibrato of DCO-2. The LFO mod is still applied via the joystick. 4132 4133DE 38 global detune will apply both temperature sensitivity to each oscillator 4134but also fatten out the harmonics by detuning them independently. It is only 4135calculated at 'note on' which can be misleading - it has no effect on existing 4136notes which is intentional if misleading. 4137 4138DE 57 is a bitmask for the three envelopes to define which ones will give a 4139response to velocity with a default to '3' for velocity tracking oscillator 4140gain: 4141 4142 value DEG1 DEG2 DEG3 4143 DCO1 DCO2 FILT 4144 4145 0 - - - 4146 1 V - - 4147 2 - V - 4148 3 V V - 4149 4 - - V 4150 5 V - V 4151 6 - V V 4152 7 V V V 4153 4154This gives some interesting velocity tracking capabilities where just one osc 4155can track velocity to introduce harmonic content keeping the filter at a fixed 4156cutoff frequence. Having a bit of detune applied globally and locally will keep 4157the sound reasonably fat for each oscillator. 4158 4159The filter envelope does not track velocity for any of the distributed voices, 4160this was intentional since when using high resonance it is not desirable that 4161the filter cutoff changes with velocity, it tends to be inconsistently 4162disonant. 4163 4164If you want to use this synth with controller mappings then map the value 4165entry pot to your easiest to find rotary, then click the mouse on the membrane 4166switch to select which parameter you want to adjust with that control each time. 4167The emulator is naturally not limited to just 4/8 voices, you can request more 4168in which case single oscillator will give you the requested number of voices 4169and double will give you half that amount. 4170 4171The Bristol Poly-800 is dedicated to Mark. 4172 4173 4174 4175 4176 Baumann BME-700 4177 --------------- 4178 4179This unusual German synth had a build volume of about 500 units and only one 4180useful source of information could be found on it: a report on repair work for 4181one of the few existing examples at www.bluesynths.com. The BME systems were 4182hand built and judging by some reports on build quality may have been sold in 4183kit form. The unit was produced in the mid 1970's. 4184 4185The synth has a very interesting design, somewhat reminiscent of the Moog Sonic 4186and Explorer synths. It has two modulating LFO with fairly high top frequency, 4187two filter and two envelopes. The envelopes are either AR or ASR but they can 4188be mixed together to generate amongst other features an ADSR, very innovative. 4189There is only one oscillator but the sound is fattened out by the use of two 4190parallel filters, one acting as a pure resonator and the other as a full VCF. 4191 4192The synth has been left with a minimum of overhead. There are just 8 memory 4193locations on the front panel with Load, Save and Increment buttons and one 4194panel of options to adjust a few parameters on the oscillator and filters. It 4195is possible to get extra memories by loading banks with -load: if you request 4196starting in memory #21 the emulator will stuff 20 into the bank and 1 into the 4197memory location. There is no apparant midi channel selector, use -channel <n> 4198and then stay on it. This could have been put into the options panel however 4199having midi channel in a memory is generally a bad idea. 4200 4201 A. MOD 4202 4203 Two LFO: 4204 4205 frequency from 0.1 to 100 Hz 4206 Triangle and Square wave outputs 4207 4208 Mix control 4209 4210 Mod-1/2 into the VCO FM 4211 Env-1/Mod-2 into the VCO FM 4212 4213 B. Oscillator 4214 4215 Single VCO 4216 4217 Glide 0 to 10s, on/off. 4218 PW Man: 5 to 50% duty cycle 4219 Auto depth: 4220 4221 Envelope-1 4222 Mod-1, Mod-1/2, Tri/Square 4223 4224 Vibrato depth 4225 Tuning 4226 8', 4', 16' transposition 4227 4228 Shape 4229 4230 continuous control from Square to Tri wave. 4231 4232 Mix of noise or VCO output 4233 4234 C. Res Filter 4235 4236 Sharp (24db/Oct), Flat (12dB/Oct) 4237 5 frequency switches 4238 4239 D. Envelopes 4240 4241 Two envelopes 4242 4243 Rise time 4244 Fall Time 4245 AR/ASR selector 4246 4247 Two independent mixes of Env, for VCF and VCA. 4248 4249 E. Filter 4250 4251 Frequency 4252 Resonance 4253 Env/Mod selector 4254 4255 Modulation 4256 4257 KBD tracking 4258 Mod-1 or Mod-2, Tri/Square 4259 4260 F. Amplifier 4261 4262 Mix resonator/filter. 4263 Volume 4264 4265 Mod depth 4266 4267 Mod-1 or Mod-2, Tri/Square 4268 4269The oscillator is implemented as a non-resampling signal generator, this means 4270it uses heuristics to estimate the wave at any given time. The harmonic content 4271is a little thin and although the generation method seems to be correct in how 4272it interprets signal ramps and drains from an analogue circuit this is one area 4273of improvement in the emulator. There are options to produce multiple waveforms 4274described below. 4275 4276The resonant filter is implemented with a single Houvilainen and actually only 4277runs at 24dB/Oct. There are controls for remixing the different taps, a form 4278of feedforward and when in 'Flat' mod there is more remixing of the poles, this 4279does generate a slower roll off but gives the signal a bit more warmth than a 4280pure 12dB/Oct would. 4281 4282 4283There is a selector in the Memory section to access some options: 4284 4285 G. Options 4286 4287 LFO 4288 4289 Synchronise wave to key on events 4290 Multi LFO (per voice). 4291 4292 Oscillator 4293 4294 Detune (temperature sensitivity) 4295 Multi - remix 8' with 16' or 4'. 4296 4297 Noise 4298 4299 Multi Noise (per voice). 4300 White/Pink 4301 Pink Filter 4302 4303 ResFilter 4304 4305 Sharp Resonance/Remix 4306 Flat Resonance/Remix 4307 4308 Envelope 4309 4310 Velocity Sensitive 4311 Rezero for note on 4312 Gain 4313 4314 Filter 4315 4316 Remix 4317 KBD tracking depth 4318 4319The emulator probably gives the best results with the following: 4320 4321startBristol -bme700 -mono -hnp -retrig -channel 1 4322 4323This gives a monophonic emulation with high note preference and multiple 4324triggers. 4325 4326The options from section G are only loaded under two circumstances: at system 4327start from the first selected memory location and if the Load button is given 4328a DoubleClick. All other memory load functions will inherrit the settings that 4329are currently active. 4330 4331 4332 4333 4334 Bristol BassMaker 4335 ----------------- 4336 4337The BassMaker is not actually an emulator, it is a bespoke sequencer design but 4338based on the capabilities of some of the early analogue sequencers such as the 4339Korg SQ-10. Supplying this probably leaves bristol open to a lot of feature 4340requests for sequencer functionaliity and it is stated here that the BassMaker 4341is supposed to be simple so excess functionality will probably be declined as 4342there are plenty of other sequencing applications that can provide a richer 4343feature set. 4344 4345The main page gives access to a screen of controls for 16 steps and a total of 43464 pages are available for a total of 64 steps. The pages are named 'A' through 4347'D'. Each step has 5 options: 4348 4349 Note: one octave of note selection 4350 Transpose: +/- one octave transposition of the note. 4351 Volume: MIDI note velocity 4352 Controller: MIDI modulation, discussed further below 4353 Triggers: Note On/Off enablers 4354 4355The trigger button gives 4 options indicated by the LED: 4356 4357 off: note on/off are sent 4358 red: only send note_on 4359 green: only send note_off 4360 yellow: do not send note on/off 4361 4362The 'Controllers' setting has multiple functions which can be selected from 4363the menu as explained below. The options available are as follows: 4364 4365 Send semitone tuning 4366 4367 Send glide rate 4368 4369 Send modwheel 4370 4371 Send expression pedal (controller value) 4372 4373 Send Note: the controller will be 12 discrete steps as per the 'Note' 4374 setting and this note will be sent on the Secondary MIDI channel. 4375 4376The semitone tuning and glide work for the majority of the emulations. Some do 4377not support fine tune controls (Vox, Hammond, others). If you are missing these 4378capabilities for specific emulators raise a change request on Sourceforge.net. 4379 4380At the top of the window there is a panel to manage the sequencer. It has the 4381following functions: 4382 4383 Speed: step rate through the notes 4384 DutyCycle: ratio of note-on to note-off 4385 4386 Start/Pause 4387 Stop: stop and return to first step/page 4388 4389 Direction: 4390 Up 4391 Down 4392 Up/Down 4393 Random 4394 4395 Select: which of the pages to include in the sequence. 4396 Edit: which page is currently displayed to be edited. 4397 4398 Memory: 4399 0..9 key entry buttons, 1000 memories available 4400 Load 4401 Save: doubleclick to save current sequence 4402 4403 Menu Panel 4404 Up, Down menu 4405 Function (return to previous level) 4406 Enter: enter submenu or enter value if in submenu 4407 4408The menu consists of several tables, these can be stepped through using the Up 4409and Down arrows to move through the menu and the 'Enter' arrow to select a sub 4410menu or activate any option. The 'Fn' button returns one level: 4411 4412 Memory: 4413 4414 Find next free memory upwards 4415 Find next memory upwards 4416 Find next memory downwards 4417 4418 Copy: 4419 4420 Copy current edit page to 'A', 'B', 'C' or 'D'. 4421 4422 Control - Set the control value to send: 4423 4424 semitone tuning 4425 glide rate 4426 modwheel 4427 expression pedal (controller value) 4428 note events 4429 4430 First midi channel 4431 4432 Primary midi channel for note events 4433 4434 Second midi channel 4435 4436 Secondary midi channel when 'Control' configured to 'Note' events. 4437 4438 Global Transpose 4439 4440 Transpose the whole sequence up or down 12 semitones 4441 4442 Clear - configure default value for all of the: 4443 4444 Notes to zero 4445 Transpose to zero (midpoint) 4446 Volume to 0.8 4447 Control to midpoint 4448 Triggers to on/off 4449 4450As of the first release in 0.30.8 large parts of the Controllers functionality 4451was only lightly tested. If you do not get the results you anticipate you may 4452require a fix. 4453 4454 4455 4456 4457 Bristol SID 4458 ----------- 4459 4460In release 0.40 bristol introduced a piece of code that emulated the Commodore 4461C64 6581 SID chip. The interface uses byte settings of the 31 chip registers to 4462be close to the original plus some floating point IO for extracting the audio 4463signal and configuring some analogue parameters and the 'softSID' is clocked 4464by the sample extraction process. 4465 4466The chip uses integer maths and logic for the oscillators, ring mod, sync and 4467envelopes and emulates the analogue components of the 6581 with floating point 4468code, for the filter and S/N generation. 4469 4470The oscillators will run as per the original using a single phase accumulator 4471and 16 bit frequency space. All the waveforms are extracted logically from the 4472ramp waveform generated by the phase accumulation. Sync and RingMod are also 4473extracted with the same methods. The noise generation is exor/add as per the 4474original however the noise signal will not degenerate when mixing waveforms. 4475The output waves are ANDed together. The bristol control register has an option 4476for Multi waveforms and when selected each oscillator will have its own phase 4477accumulator, can have a detune applied and will be mixed by summation rather 4478than using an AND function. 4479 4480The envelope is an 8 bit up/down counter with a single gate bit. All the 4 bit 4481parameters give rates taken from the chip specifications including the slightly 4482exponential decay and release. Attack is a linear function and the sustain level 4483can only be decreased when active as the counter also refuses to count back up 4484when passed its peak. 4485 4486The filter implements a 12dB/Octave multimode chamberlain filter providing LP, 4487BP and HP signals. This is not the best filter in the world however neither was 4488the original. An additional 24dB/Octave LP filter has been added, optionally 4489available and with feedforward to provide 12/18dB signals. Between them the 4490output can be quite rich. 4491 4492The emulator provides some control over the 'analogue' section. The S/N ratio 4493can be configured from inaudible (just used to prevent denormal of the filter) 4494up to irritating levels. Oscillator leakage is configurable from none up to 4495audible levels and the oscillator detune is configurable in cents although 4496this is a digital parameter and was not a part of the original. 4497 4498Voice-3 provides an 8 bit output of its oscillator and envelope via the normal 4499output registers and the otherwise unused X and Y Analogue registers contain 4500the Voice-1 and Voice-2 oscillator output. 4501 4502The bristol -sid emulator uses two softSID, one generating three audio voices 4503and a second one providing modulation signals by sampling the voice-3 osc and 4504env outputs and also by configuring voice-1 to generate noise to the output, 4505resampling this noise and gating it from voice-3 to get sample and hold. This 4506would have been possible with the original as well if the output signal were 4507suitably coupled back on to one of the X/Y_Analogue inputs. 4508 4509The emulator has several key assignment modes. The emulator is always just 4510monophonic but uses internal logic to assign voices. It can be played as a big 4511mono synth with three voices/oscillators, polyphonically with all voices either 4512sounding the same or optionally configured individually, and as of this release 4513a single arpeggiating mode - Poly-3. Poly-3 will assign Voice-1 to the lowest 4514note, voice-3 to the highest note and will arpeggiate Voice-2 through all other 4515keys that are pressed with a very high step rate. This is to provide some of 4516the sounds of the original C64 where fast arpeggiation was used to sounds 4517chords rather than having to use all the voices. This first implementation 4518does not play very well in Poly-3, a subsequent release will probably have a 4519split keyboard option where one half will arpeggiate and the other half will 4520play notes. 4521 4522This is NOT a SID player, that would require large parts of the C64 to also be 4523emulated and there are plenty of SID players already available. 4524 4525Bristol again thanks Andrew Coughlan, here for proposing the implementation of 4526a SID chip which turned out to be a very interesting project. 4527 4528 4529 4530 4531 4532For the sake of being complete, given below is the verbose help output 4533 4534 4535 4536A synthesiser emulation package. 4537 4538 You should start this package with the startBristol script. This script 4539 will start up the bristol synthesiser binaries evaluating the correct 4540 library paths and executable paths. There are emulation, synthesiser, 4541 operational and GUI parameters: 4542 4543 Emulation: 4544 4545 -mini - moog mini 4546 -explorer - moog voyager 4547 -voyager - moog voyager electric blue 4548 -memory - moog memory 4549 -sonic6 - moog sonic 6 4550 -mg1 - moog/realistic mg-1 concertmate 4551 -hammond - hammond module (deprecated, use -b3) 4552 -b3 - hammond B3 (default) 4553 -prophet - sequential circuits prophet-5 4554 -pro52 - sequential circuits prophet-5/fx 4555 -pro10 - sequential circuits prophet-10 4556 -pro1 - sequential circuits pro-one 4557 -rhodes - fender rhodes mark-I stage 73 4558 -rhodesbass - fender rhodes bass piano 4559 -roadrunner - crumar roadrunner electric piano 4560 -bitone - crumar bit 01 4561 -bit99 - crumar bit 99 4562 -bit100 - crumar bit + mods 4563 -stratus - crumar stratus synth/organ combo 4564 -trilogy - crumar trilogy synth/organ/string combo 4565 -obx - oberheim OB-X 4566 -obxa - oberheim OB-Xa 4567 -axxe - arp axxe 4568 -odyssey - arp odyssey 4569 -arp2600 - arp 2600 4570 -solina - arp/solina string ensemble 4571 -polysix - korg polysix 4572 -poly800 - korg poly-800 4573 -monopoly - korg mono/poly 4574 -ms20 - korg ms20 (unfinished: -libtest only) 4575 -vox - vox continental 4576 -voxM2 - vox continental super/300/II 4577 -juno - roland juno-60 4578 -jupiter - roland jupiter-8 4579 -bme700 - baumann bme-700 4580 -bm - bristol bassmaker sequencer 4581 -dx - yamaha dx-7 4582 -cs80 - yamaha cs-80 (unfinished) 4583 -sidney - commodore-64 SID chip synth 4584 -melbourne - commodore-64 SID polyphonic synth (unfinished) 4585 -granular - granular synthesiser (unfinished) 4586 -aks - ems synthi-a (unfinished) 4587 -mixer - 16 track mixer (unfinished: -libtest only) 4588 4589 Synthesiser: 4590 4591 -voices <n> - operate with a total of 'n' voices (32) 4592 -mono - operate with a single voice (-voices 1) 4593 -lnp - low note preference (-mono) 4594 -hnp - high note preference (-mono) 4595 -nnp - no/last note preference (-mono) 4596 -retrig - monophonic note logic legato trigger (-mono) 4597 -lvel - monophonic note logic legato velocity (-mono) 4598 -channel <c> - initial midi channel selected to 'c' (default 1) 4599 -lowkey <n> - minimum MIDI note response (0) 4600 -highkey <n> - maximum MIDI note response (127) 4601 -detune <%> - 'temperature sensitivity' of emulation (0) 4602 -gain <gn> - emulator output signal gain (default 1) 4603 -pwd <s> - pitch wheel depth (2 semitones) 4604 -velocity <v> - MIDI velocity mapping curve (510) (-mvc) 4605 -glide <s> - MIDI glide duration (5) 4606 -emulate <name> - search for the named synth or exit 4607 -register <name> - name used for jack and alsa device regisration 4608 -lwf - emulator lightweight filters 4609 -nwf - emulator default filters 4610 -wwf - emulator welterweight filters 4611 -hwf - emulator heavyweight filters 4612 -blo <h> - maximum # band limited harmonics (31) 4613 -blofraction <f> - band limiting nyquist fraction (0.8) 4614 -scala <file> - read the scala .scl tonal mapping table 4615 4616 User Interface: 4617 4618 -quality <n> - color cache depth (bbp 2..8) (6) 4619 -grayscale <n> - color or BW display (0..5) (0 = color) 4620 -antialias <n> - antialias depth (0..100%) (30) 4621 -aliastype <s> - antialias type (pre/texture/all) 4622 -opacity <n> - opacity of the patch layer 20..100% (50) 4623 -scale <s> - initial windowsize, fs = fullscreen (1.0) 4624 -width <n> - the pixel width of the GUI window 4625 -autozoom - flip between min and max window on Enter/Leave 4626 -raise - disable auto raise on max resize 4627 -lower - disable auto lower on min resize 4628 -rud - constrain rotary tracking to up/down 4629 -pixmap - use the pixmap interface rather than ximage 4630 -dct <ms> - double click timeout (250 ms) 4631 -tracking - disable MIDI keyboard tracking in GUI 4632 -load <m> - load memory number 'm' (default 0) 4633 -import <pathname> - import memory from file into synth 4634 -mbi <m> - master bank index (0) 4635 -activesense <m> - active sense rate (2000 ms) 4636 -ast <m> - active sense timeout (15000 ms) 4637 -mct <m> - midi cycle timeout (50 ms) 4638 -ar|-aspect - ignore emulator requested aspect ratio 4639 -iconify - start with iconified window 4640 -window - toggle switch to enable X11 window interfacen 4641 -cli - enable command line interface 4642 -libtest - gui test option, engine not invoked 4643 4644 Gui keyboard shortcuts: 4645 4646 <Ctrl> 's' - save settings to current memory 4647 <Ctrl> 'l' - (re)load current memory 4648 <Ctrl> 'x' - exchange current with previous memory 4649 <Ctrl> '+' - load next memory 4650 <Ctrl> '-' - load previous memory 4651 <Ctrl> '?' - show emulator help information 4652 <Ctrl> 'h' - show emulator help information 4653 <Ctrl> 'r' - show application readme information 4654 <Ctrl> 'k' - show keyboard shortcuts 4655 <Ctrl> 'p' - screendump to /tmp/<synth>.xpm 4656 <Ctrl> 't' - toggle opacity 4657 <Ctrl> 'o' - decrease opacity of patch layer 4658 <Ctrl> 'O' - increase opacity of patch layer 4659 <Ctrl> 'w' - display warranty 4660 <Ctrl> 'g' - display GPL (copying conditions) 4661 <Shift> '+' - increase window size 4662 <Shift> '-' - decrease window size 4663 <Shift> 'Enter'- toggle window between full screen size 4664 'UpArrow' - controller motion up (shift key accelerator) 4665 'DownArrow' - controller motion down (shift key accelerator) 4666 'RightArrow' - more controller motion up (shift key accelerator) 4667 'LeftArrow' - more controller motion down (shift key accelerator) 4668 4669 Operational: 4670 4671 General: 4672 4673 -engine - don't start engine (connect to existing engine) 4674 -gui - don't start gui (only start engine) 4675 -server - run engine as a permanant server 4676 -daemon - run engine as a detached permanant server 4677 -log - redirect diagnostic to $HOME/.bristol/log 4678 -syslog - redirect diagnostic to syslog 4679 -console - log all messages to console (must be 1st option) 4680 -cache <path> - memory and profile cache location (~/.bristol) 4681 -exec - run all subprocesses in background 4682 -debug <1-16> - debuging level (0) 4683 -readme [-<e>] - show readme [for emulator <e>] to console 4684 -glwf - global lightweight filters - no overrides 4685 -host <h> - connect to engine on host 'h' (localhost) 4686 -port <p> - connect to engine on TCP port 'p' (default 5028) 4687 -quiet - redirect diagnostic output to /dev/null 4688 -gmc - open a MIDI connection to the brighton GUI 4689 -oss - use OSS defaults for audio and MIDI 4690 -alsa - use ALSA defaults for audio and MIDI (default) 4691 -jack - use Jack defaults for audio and MIDI 4692 -jsmuuid <UUID>- jack session unique identifier 4693 -jsmfile <path>- jack session setting path 4694 -jsmd <ms> - jack session file load delay (5000) 4695 -session - disable session management 4696 -jdo - use separate Jack clients for audio and MIDI 4697 -osc - use OSC for control interface (unfinished) 4698 -forward - disable MIDI event forwarding globally 4699 -localforward - disable emulator gui->engine event forwarding 4700 -remoteforward - disable emulator engine->gui event forwarding 4701 -o <filename> - Duplicate raw audio output data to file 4702 -nrp - enable NPR support globally 4703 -enrp - enable NPR/DE support in engine 4704 -gnrp - enable NPR/RP/DE support in GUI 4705 -nrpcc <n> - size of NRP controller table (128) 4706 4707 Audio driver: 4708 4709 -audio [oss|alsa|jack] - audio driver selection (alsa) 4710 -audiodev <dev> - audio device selection 4711 -count <samples> - sample period count (256) 4712 -outgain <gn> - digital output signal gain (default 4) 4713 -ingain <gn> - digital input signal gain (default 4) 4714 -preload <periods> - configure preload buffer count (default 4) 4715 -rate <hz> - sample rate (44100) 4716 -priority <p> - audio RT priority, 0=no realtime (75) 4717 -autoconn - attempt jack port auto-connect 4718 -multi <c> - register 'c' IO channels (jack only) 4719 -migc <f> - multi IO input gain scaling (jack only) 4720 -mogc <f> - multi IO output gain scaling (jack only) 4721 4722 Midi driver: 4723 4724 -midi [oss|[raw]alsa|jack] - midi driver selection (alsa) 4725 -mididev <dev> - midi device selection 4726 -seq - use the ALSA SEQ interface (default) 4727 -mididbg - midi debug-1 enable 4728 -mididbg2 - midi debug-2 enable 4729 -sysid - MIDI SYSEX system identifier 4730 4731 LADI driver (level 1 compliant): 4732 4733 -ladi brighton - only execute LADI in GUI 4734 -ladi bristol - only execute LADI in engine 4735 -ladi <memory> - LADI state memory index (1024) 4736 4737 Audio drivers are PCM/PCM_plug or Jack. Midi drivers are either OSS/ALSA 4738 rawmidi interface, or ALSA SEQ. Multiple GUIs can connect to the single 4739 audio engine which then operates multitimbrally. 4740 4741 The LADI interfaces does not use a state file but a memory in the normal 4742 memory locations. This should typically be outside of the range of the 4743 select buttons for the synth and the default of 1024 is taken for this 4744 reason. 4745 4746 Examples: 4747 4748 startBristol 4749 4750 Print a terse help message. 4751 4752 startBristol -v -h 4753 4754 Hm, if you're reading this you found these switches already. 4755 4756 startBristol -mini 4757 4758 Run a minimoog using ALSA interface for audio and midi seq. This is 4759 equivalent to all the following options: 4760 -mini -alsa -audiodev plughw:0,0 -midi seq -count 256 -preload 8 4761 -port 5028 -voices 32 -channel 1 -rate 44100 -gain 4 -ingain 4 4762 4763 startBristol -alsa -mini 4764 4765 Run a minimoog using ALSA interface for audio and midi. This is 4766 equivalent to all the following options: 4767 -mini -audio alsa -audiodev plughw:0,0 -midi alsa -mididev hw:0 4768 -count 256 -preload 8 -port 5028 -voices 32 -channel 1 -rate 44100 4769 4770 startBristol -explorer -voices 1 -oss 4771 4772 Run a moog explorer as a monophonic instrument, using OSS interface for 4773 audio and midi. 4774 4775 startBristol -prophet -channel 3 4776 4777 Run a prophet-5 using ALSA for audio and midi on channel 3. 4778 4779 startBristol -b3 -count 512 -preload 2 4780 4781 Run a hammond b3 with a buffer size of 512 samples, and preload two 4782 such buffers before going active. Some Live! cards need this larger 4783 buffer size with ALSA drivers. 4784 4785 startBristol -oss -audiodev /dev/dsp1 -vox -voices 8 4786 4787 Run a vox continental using OSS device 1, and default midi device 4788 /dev/midi0. Operate with just 8 voices. 4789 4790 startBristol -b3 -audio alsa -audiodev plughw:0,0 -seq -mididev 128.0 4791 4792 Run a B3 emulation over the ALSA PCM plug interface, using the ALSA 4793 sequencer over client 128, port 0. 4794 4795 startBristol -juno & 4796 startBristol -prophet -channel 2 -engine 4797 4798 Start two synthesisers, a juno and a prophet. Both synthesisers will 4799 will be executed on one engine (multitimbral) with 32 voices between 4800 them. The juno will be on default midi channel (1), and the prophet on 4801 channel 2. Output over the same default ALSA audio device. 4802 4803 startBristol -juno & 4804 startBristol -port 5029 -audio oss -audiodev /dev/dsp1 -mididev /dev/midi1 4805 4806 Start two synthesisers, a juno on the first ALSA soundcard, and a 4807 mini on the second OSS soundcard. Each synth is totally independent 4808 and runs with 32 voice polyphony (looks nice, not been tested). 4809 4810The location of the bristol binaries can be specified in the BRISTOL 4811environment variable. Private memory and MIDI controller mapping files can 4812be found in the directory BRISTOL_CACHE and defaults to $HOME/.bristol 4813 4814Setting the environment variable BRISTOL_LOG_CONSOLE to any value will result 4815in the bristol logging output going to your console window without formatted 4816timestamps 4817 4818Korg Inc. of Japan is the rightful owner of the Korg and Vox trademarks, and 4819the Polysix, Mono/Poly, Poly-800, MS-20 and Continental tradenames. Their own 4820Vintage Collection provides emulations for a selection of their classic 4821synthesiser range, this product is in no manner related to Korg other than 4822giving homage to their great instruments. 4823 4824Bristol is in no manner associated with any of the original manufacturers of 4825any of the emulated instruments. All names and trademarks are property of 4826their respective owners. 4827 4828 author: Nick Copeland 4829 email: nickycopeland@hotmail.com 4830 4831 http://bristol.sourceforge.net 4832 4833