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SEQUENTIAL/DSI => Prophet => Prophet Rev2 => Topic started by: creativespiral on March 13, 2019, 09:32:25 AM

Title: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 13, 2019, 09:32:25 AM
I found a way to better capture the character of classic VCO analog poly synths with the Prophet Rev2.   It's not a magic bullet, and it can't make a Curtis filter sound like a Moog ladder, but it can produce some really organic, warm, lush patches that sound a bit more authentic.

This method can also be used to model real world analog/acoustic instruments more realistically  (woodwinds, brass, strings, etc).   

Voice Component Modeling:

http://www.VoiceComponentModeling.com/vcm.aspx

It's focused on virtual voice-by-voice modeling down to the component level, and allows a high level of definition to polyphonic sounds.   

Much of the character of a given instrument or ensemble comes from small imperfections on a voice-by-voice basis.   This method allows you to virtually allocate a voice count (ie: 8-voices CS80,  6-voices MemoryMoog, etc...), and dial in specific characteristics on a per-voice basis.

If you have poly-voice patches using a decent amount of Osc Slop, you can probably use this method to improve their character.   Osc Slop is a tool that can give your Rev2 patches some voice definition, but it does so in a random nature (multiple free running LFOs), with a lot of exaggerated tuning motion per oscillator, especially once you get into medium to higher values.

I've found that in patches where I used Osc Slop for voice-definition before, I now cut the Osc Slop down by 80% or so, and use this voice-modeling method to produce the majority of voice-by-voice character... then I may sprinkle just a bit of Osc Slop back in, for just a tiny bit of randomness and tuning motion.

In addition to oscillator tuning, you can target any other mod destination or macro with per-voice offsets... allowing you to create poly-voice instruments full of character (minor imperfections from voice-to-voice).

Check out the web page I set up for a bunch more details and a full write up.   I'm working on a bank of sounds now.   In the meantime, if you want some sample patches / VCM templates, send me your email and I'll send you a mini-bank with some examples, and templates for 4-voice, 5-voice, 6-voice and 8-voice patches with all the modulation wiring set up.

http://www.VoiceComponentModeling.com/vcm.aspx (http://www.VoiceComponentModeling.com/vcm.aspx)

Part 3 addresses Prophet Rev2 implementation and Part 4 gives and overview of the benefits.

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: psionic11 on March 13, 2019, 02:36:28 PM
Great job on your website!  I can see you put a lot of research into this.  This is one of those discoveries that you look back on and think "of course, it makes so much sense in hindsight".

I've never worked with the gated sequencer with the Rev2, guess I'll have to look into it now.  I just requested access to your templates via email.

It's interesting to note that you scoured posts on the characteristics of various classics -- the voice allocation of Jupiter 8s, the voicecard tuning on Memorymoogs, etc.  I'm particularly curious to find out what kinds of envelopes old classics used.  Did the SEM modules have logarithmic curves?  Were the Rolands more linear?  Were the attack and decay stages different from each other?  Did envelope amount affect those curves?

Do you have any links that might address those issues?  It's a theme that was brought up often in the Moog One thread over at GS.  Thanks.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Quatschmacher on March 13, 2019, 03:00:21 PM
I found a way to better capture the character of classic VCO analog poly synths with the Prophet Rev2.   It's not a magic bullet, and it can't make a Curtis filter sound like a Moog ladder, but it can produce some really organic, warm, lush patches that sound a bit more authentic.

This method can also be used to model real world analog/acoustic instruments more realistically  (woodwinds, brass, strings, etc).   

Voice Component Modeling:

http://www.VoiceComponentModeling.com/vcm.aspx

It's focused on virtual voice-by-voice modeling down to the component level, and allows a high level of definition to polyphonic sounds.   

Much of the character of a given instrument or ensemble comes from small imperfections on a voice-by-voice basis.   This method allows you to virtually allocate a voice count (ie: 8-voices CS80,  6-voices MemoryMoog, etc...), and dial in specific characteristics on a per-voice basis.

If you have poly-voice patches using a decent amount of Osc Slop, you can probably use this method to improve their character.   Osc Slop is a tool that can give your Rev2 patches some voice definition, but it does so in a random nature (multiple free running LFOs), with a lot of exaggerated tuning motion per oscillator, especially once you get into medium to higher values.

I've found that in patches where I used Osc Slop for voice-definition before, I now cut the Osc Slop down by 80% or so, and use this voice-modeling method to produce the majority of voice-by-voice character... then I may sprinkle just a bit of Osc Slop back in, for just a tiny bit of randomness and tuning motion.

In addition to oscillator tuning, you can target any other mod destination or macro with per-voice offsets... allowing you to create poly-voice instruments full of character (minor imperfections from voice-to-voice).

Check out the web page I set up for a bunch more details and a full write up.   I'm working on a bank of sounds now.   In the meantime, if you want some sample patches / VCM templates, send me your email and I'll send you a mini-bank with some examples, and templates for 4-voice, 5-voice, 6-voice and 8-voice patches with all the modulation wiring set up.

http://www.VoiceComponentModeling.com/vcm.aspx (http://www.VoiceComponentModeling.com/vcm.aspx)

Part 3 addresses Prophet Rev2 implementation and Part 4 gives and overview of the benefits.

Great job and an interesting read.

You mentioned about the current lack of ability to mimic voice stealing behaviour. Could that not be done by defeating voices on the synth? (I know the P6/OB-6 have that feature and presume that Rev 2 would too.) That way, of modelling a P5, you can simply defeat the sixth and higher voices. You’d have to power cycle the synth to recover the voices so it’s not an ideal solution but could be a workaround.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Blueskytech on March 13, 2019, 04:24:34 PM
Extremely well documented write up I am seriously impressed. I sent you an email.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: maxter on March 13, 2019, 05:30:56 PM
"of course, it makes so much sense in hindsight".

My exact feeling. Having used the gated sequencers quite a bit, mostly for complex melodic and rhythmic variations, I feel like I should've realized this much sooner, especially after creativespirals other, initial thread on this subject. How did I not think of using the Key Step gate-mode this way?

I will probably run with this in the same direction as when using the gated sequencers for a melodical/rhytmic context, that is combining sequencers of various lengths to build patches that don't repeat very often. I like going with 12,13,14,15 steps or 11,12,13,14, generally (avoiding 16 especially with rhythmic patterns, as it's 4 squared (which in turn is 2 squared) the most fundamental and repetitive rhythm). Taking a long time until a repeated behavior, while avoiding the 2/4/8/16. Having 4 sequencers modulating different and/or the same parameters, with different lenghts (loop points), will create results in a sense "beyond" voice allocation VCO mimicking (though VCO mimicking is more than enough). Imo DCOs should reign supreme, in this respect, from here on (if there are enough of the right modulation possibilities). Like having 15 VCOs routed through 14 filters, each repeating cyclically, for instance. Or, for example, seq1 routed + to osc1 and - to osc2, and vice versa with seq2 at different lenghts (via the LFOs in this case, at least for now  ;) ). I really hope SCI will implement a "fine tune" mod parameter eventually, to save up on the mod slots. Using 4 gated sequencers with at least 12 possible modulation destinations should be enough for some good stuff then. What I mean is this: mimicking VCOs behavior, breaking this behavior down to a couple of parameters that can be digitally controlled by LFOs mainly (as creativespiral has so excellently done), the next step would be to take this concept to the next level. Ie we could mimic the VCO character but make it even less predictable/stable than a VCO (though it WOULD actually be predictable, in the true sense), as there are more variations per tone going on simultaneously than a VCO, and each amount/depth is CONTROLLABLE (unlike VCOs)... Ie to take the studied characteristics of the behavior of the VCO, and expand on and/or modulate them further. Since, I believe, creativespiral has nailed the behavior and how to recreate it, it is easily multiplied and/or divided and modulated, to different destinations.

I will probably make a template patch for this, so that I've got the 4 sequencers already set up, ready to go, just routing them to different destinations for each patch. And probably some of the mod matrix set up as well.

Also, the BPM knob may find a whole new purpose to me now, when using it in this context! Not to forget switching between gate modes can sometimes be useful too, especially when midi synced to an external sequencer.

Loads of fun to come! Huge thank you for your solid and thorough work, creativespiral! You ought to be hired by [insert synth brand here] to design the one DCO synth to rule them all. I know I'd buy it at least!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 13, 2019, 10:32:29 PM
Great job on your website!  I can see you put a lot of research into this.  This is one of those discoveries that you look back on and think "of course, it makes so much sense in hindsight".

I've never worked with the gated sequencer with the Rev2, guess I'll have to look into it now.  I just requested access to your templates via email.

It's interesting to note that you scoured posts on the characteristics of various classics -- the voice allocation of Jupiter 8s, the voicecard tuning on Memorymoogs, etc.  I'm particularly curious to find out what kinds of envelopes old classics used.  Did the SEM modules have logarithmic curves?  Were the Rolands more linear?  Were the attack and decay stages different from each other?  Did envelope amount affect those curves?

Do you have any links that might address those issues?  It's a theme that was brought up often in the Moog One thread over at GS.  Thanks.

Thanks!   I haven't compiled details on envelopes of old synths... most of my research was focused on osc tuning tendencies and voice allocation.   This page on Wikipedia does have a good list of Curtis (CEM) and Solid State Micro (SSM) integrated circuits (IC chips) -- with a decent amount of details on which synths used the chips... so it's a good starting point to look up further details.   For instance, Prophet-5 Rev1/2 used SSM2050 Envelopes, but the Rev3 used CEM3310s.  Next step would be to lookup those chip numbers and try and find specific measurements on timing/curves/behavior.

https://en.wikipedia.org/wiki/CEM_and_SSM_chips_in_synthesizers

I know you mentioned an interest in details of Recursive Envelope Modulation on the Rev... that is something I've done some testing on and plan to add to the Appendix F thread at some point... I have a few topics that are partially documented...  Just need to spend some additional time to write up the specifics, take screen grabs, etc..   Between work and fam, it has been hard for me to block out a lot of music and sound design time lately.




Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 13, 2019, 10:44:56 PM
Great job and an interesting read.

You mentioned about the current lack of ability to mimic voice stealing behaviour. Could that not be done by defeating voices on the synth? (I know the P6/OB-6 have that feature and presume that Rev 2 would too.) That way, of modelling a P5, you can simply defeat the sixth and higher voices. You’d have to power cycle the synth to recover the voices so it’s not an ideal solution but could be a workaround.

Thanks Quatschmacher.   I don't think the Rev2 has a way to defeat voices... That may be a VCO only "feature", in case one of your voices is dead or can't be tuned within a reasonable threshold.   

We get sort of the best of both worlds with virtual voice modeling... we can define whatever voice count we want and won't experience voice stealing (unless physical polyphony on board is exceeded)... if the virtual voice count is exceeded, the new voice will just copy the value of the oldest/next voice in line.   Of course if we truly wanted that extra realism of voice stealing, it could possibly be added with future manufacturer developments... though I'd like to see a "Key Step, Reset" and "Key Step, Backtrack" implemented before that... as mentioned in last section of the website I setup - that would allow modeling the Jupiter-8 voice allocation scheme, and be better for acoustic ensemble modeling. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 13, 2019, 10:50:19 PM
I will probably make a template patch for this, so that I've got the 4 sequencers already set up, ready to go, just routing them to different destinations for each patch. And probably some of the mod matrix set up as well.

Loads of fun to come! Huge thank you for your solid and thorough work, creativespiral! You ought to be hired by [insert synth brand here] to design the one DCO synth to rule them all. I know I'd buy it at least!

Thanks Maxter! - excited to see and hear examples of what people make.   As for templates, I have some .syx files I can send you... or if you wanna build them yourself, its not that hard... just have to keep scaling / offsets in mind.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 13, 2019, 11:04:29 PM
The website has details for the Rev2 setup, but here's a step-by-step list to refer to if wiring this up yourself for an Init Patch:

1. Set Osc1 and Osc2 fine tuning to -31. 
This offset will allow a center-point to work from in Gated Seq setup.  Set Osc Mix to middle.

2. Setup the Gated Sequencer

a. Set Gated Seq to "Key Step" Mode

b. Gated Seq Lane 1: Will be routed/scaled to Osc 1 Freq via Mod Matrix
Set a reset at step seven (for a six voice emulation), and then dial in some random values between ~54-70 for the six steps (with 62 being centerpoint)... Don't set Gated Seq Destination... leave it to destination: none.   

c. Gated Seq Lane 2: Will be routed/scaled to Osc 2 Freq via Mod Matrix
Set a reset at the same step as sequence 1, and then dial in similar values here ~54-70... for per voice fine tuning.  Again, don't set destination here, just the per voice values and the reset on step seven.

Note:  Each incremented value will equal ~0.38 cents change to fine tuning when scaled (ie: +3 will equal a little over 1 cent sharp, and -3 would be a little under 1 cent flat.   We're using 62 as the centerpoint for this setup...  Above, we set Osc1 and Osc2 fine tuning to -31 to compensate for the centerpoint.   Value of 62 means "perfectly in tune"

3. Setup the Mod Matrix for Fine Tune Scaling of Freq:

a. Mod Matrix 1: 
Set source to Seq 1, Set destination to Osc Freq 1, Set amount to 1.

b. Mod Matrix 2: 
Set source to Seq 2, Set destination to Osc Freq 2, Set amount to 1.

Note:   The value that is passed on to the Osc Frequency is going to be a fraction of 1.   It will be the number set in the Gated Sequencer (62 for example), divided by the Max Gated Sequencer Value (125), multiplied by the Mod Matrix amount (1).   So if the value of the Gated Sequencer step is 62, we're sending on 62/125*1 = 0.496     In step one, we set offsets of -31 fine tuning for each oscillator, so the net effect of a value of 62 should cancel out the offset and we should be perfectly tuned.   

Alright, now test things out!
If its wired up correctly, then every key press should advance the Gated Sequencer by one Key Step, giving you a sort of virtual six voice instrument.   Each step of the sequence will have unique values for Osc1 and Osc2 fine tuning, giving you a slightly different detuned character per-voice.  It gives a more organic feeling, since each voice (and each osc) has unique tuning imperfections. 

Try holding down a chord, and you'll notice the natural motion/phasing associated with each oscillator having slightly different tuning.  If you tried to achieve the same sort of per-voice character using Osc Slop, you would have a bunch of randomness, and exaggerated/artificial tuning motion added onto the more natural wave motion of oscillators that have more stable tuning offsets...

If it's too wild sounding, try dialing back the Gated Seq values closer to 62 per step.  If you want more character on a per-voice basis, scale the values out further away from 62.  Remember, every 3 increments away from 62 will equal about 1 cent... so if you want lots of character, you can push tuning per osc pretty far.  If you push it too far it may sound like crap, but if you spend some time dialing in and testing values, you can get into some untamed Memory Moog type territory. 

Note:   For each step, you may want to keep the values of the #1 and #2 sequence steps somewhat close to each other, while still having slight variations.   This emulates a situation where the voice as a whole has a sharp or flat tendency, yet the oscillators still have slight offsets.   For instance, for Gated Seq 1 and 2, you might want values semi-grouped like this:
Seq 1: 61, 69, 73, 54, 71, 63
Seq 2: 64, 62, 76, 57, 67, 62

If you're willing to sacrifice two more mod slots, you can try an alternate per-voice detuning method -- modeling intonation offsets (which are very common in VCOs).  In this case, Route Mod Matrix 1 Destination to another Mod Matrix slot with a value of 1 (or -1) (ie: Dest: Matrix 3 Amount)   Now for Matrix 3, set source to Note Num, destination to Osc Freq 1 and amount to 1.   Now you have per-voice intonation offset for Osc Frequency.  You'll want to scale all the Gated sequencer value way down (between 0-12 per step maybe)... and you may need to adjust main Osc Fine Tuning to compensate for the intonation tuning...  ie: dial it in so around middle of keyboard things are close to perfect tuning, but as you get into low or high registers, then voices with higher values will have a sharp of flat tendancy (depending on whether you chose Mod Matrix 1 value of 1 or -1)

Tons of other options to try for virtual voice setups with per-voice behavior for a variety of destinations in the Osc section, but also you can target VCF, VCA, and Envelope behavior, and by using Mod Matrix scaling, you can get fine tuned variance when needed.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: osflaa on March 14, 2019, 03:16:11 AM
Thanks a lot for this!! I have followed the steps above and AB-compared the oscillator-sound (saw) with my P6. I found that the movement caused by detuning sounds very similar. The Rev2 sounds a bit brighter though, but by turning the cutoff to about 157 I think the frequency balance sounds pretty close, too (only set by ear, I have not studied the frequency curves with a spectrum analyzer).
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: maxter on March 14, 2019, 04:59:21 AM
Yes, intonation offsets will be great! I have to try this. I think this plays a major part in the VCO sound, and I'm a big fan of "stretching" the tuning on the upper and lower registers, like on a piano. I believe this is why some say the Boog is sterile, or cold, compared to the Moog, being that it's "too" well intonated. I'd suggest to those people to detune the octave intonation by just a bit, and see if that would make the difference. Another reason for hopefully getting an added fine tune mod destination, I feel like I will probably run out of mod destinations FAST by having to scale all the tuning mods with the sequencers. And a direct mod of note number - osc freq at a value of 1 is too much for me. Finer modulation would be great on many parameters, not just osc tune.

More and more thinking about that scaling modulation capability, multiplying and dividing, on the matrix that you've suggested on the request thread. It makes a ton of sense.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 14, 2019, 10:48:31 AM
Thanks a lot for this!! I have followed the steps above and AB-compared the oscillator-sound (saw) with my P6. I found that the movement caused by detuning sounds very similar. The Rev2 sounds a bit brighter though, but by turning the cutoff to about 157 I think the frequency balance sounds pretty close, too (only set by ear, I have not studied the frequency curves with a spectrum analyzer).

Thanks Osflaa, good to hear...Yeah, as mentioned in the article, its not a magic bullet to perfectly copy other VCO synths.    There will still be differences due to variations in VCF, VCA, Envelope circuit implementation and other specifics about electrical design.   But, if we were at 90% of the way there before, this may get you to 95% of the character now.   It definitely gives some more organic feel, without the artificial motion associated with Osc Slop or LFOs.   You could try out the VCO harmonic jitter modulation that I've been playing around with too.  That might get you a tiny bit closer to P6. 

https://www.youtube.com/watch?v=Amhl07TVdNM

For voice modeling, I'm as excited about real world analog/acoustic instrument modeling as emulating VCOs...  I've been working on some string, woodwind, and brass patches that just feel full of life, with these minor voice imperfections.     
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: panic on March 15, 2019, 07:05:17 AM
Spiral, a creative one you are indeed. I cannot try it out for some time, but there is something I have some doubts about:

If its wired up correctly, then every key press should advance the Gated Sequencer by one Key Step, giving you a sort of virtual six voice instrument.   Each step of the sequence will have unique values for Osc1 and Osc2 fine tuning, giving you a slightly different detuned character per-voice.  It gives a more organic feeling, since each voice (and each osc) has unique tuning imperfections. 

Try holding down a chord, and you'll notice the natural motion/phasing associated with each oscillator having slightly different tuning. 

I never used keystep mode a lot, so perhaps I am wrong, but since the gated sequencer is a per voice modulation source, the keystepping will also happen per voice I think. Meaning that, if you set it up like you describe for six voice, and then you play a six voice chord, I think all six voices will have exactly the same offset: press a first note, it will be on step one of the gated sequence - hold it and press a second note, this second voice will not be on step 2, but also on step one. Of course, after some random playing, not all voices will be one the same step anymore, and you will have per voice variation (but not in the exact way you want, not in a controlable six voice variation way). In unison, yes, it will work as you want, but you can't play chords.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: maxter on March 15, 2019, 07:28:59 AM
That's not the way key step works. Each pressed key, or incoming midi note, does indeed advance the sequencers one step. Which enables running external sequencers through it and altering/offsetting those sequences in different ways with the sequencers, each note advancing the sequencers one step. It's possible to make some semi-"generative" melodies this way.

EDIT: I may be wrong, just tried this out and got different results than expected after triggering more than one voice simultaneously. It seems that you're right on this one, panic. I'd like to test some more, but don't have the time right now.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: panic on March 15, 2019, 07:55:23 AM
Maxter, so you say it is not how I describe? so that would mean that each keypress moves the gated sequencer for every voice at once? Not what I expected/remembered, but always glad to be proven wrong. So what happens when you press one note and hold it, then press a second one? Voice 2 goes to step 2, but voice one doesn't move and stay one step one? Seems difficult to implement, kudos to sequential.

Edit: didn't see your edit, and reading back my post it sounds a bit sarcastic, which was not my intent, I was sincerely surprised.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: maxter on March 15, 2019, 08:25:22 AM
Well, had time to do just a little more testing. It does indeed work the way creativespiral intended. If you switch mode and then back, the sequencers get off-set somehow.

I can't get my head around how the sequencers are set up right now. If setting the mode to something else, triggering a few notes, back to key-step, i get mostly repeating patterns of 8x3, for sequencers of 6 steps...

EDIT: It's just my 8 voices cycling, with different voice sequencers off-set by being triggered in a different mode and then stopped on different steps. Then continuing their respective cycle in key-step mode. The voices come in different order 3 times, repeating after 3 8-voice cycles = 4 cycles of 6-step sequencers.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: philroyjenkins on March 15, 2019, 08:50:06 AM
The gated seq seems to work as suggested for poly sequencing.

The only slight catch for the purpose of the VCM efforts would be that the gated seq doesn't care to skip over a certain step if you holding that note elsewhere, making it not a perfectly cyclical voice model but honestly this is pretty trivial.

https://drive.google.com/open?id=1Uptmn--_I2OgTyvqpjy828mUybizdX3X

Here is an example of the gated seq in its simplest form. I have a self osc filter that isn't keytracked (every note is the same) and set the gated seq up to raise the pitch every key press. I try to demo some it with some different behaviors of playing.



Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: bldrman on March 16, 2019, 06:41:08 AM
Really nice work! But what is the difference here using this method instead of using one or two LFO's with destination OSC SLOP? Set LFO1 to Triangle and LFO to Random both having OSC SLOP as DESTINATION.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Quatschmacher on March 17, 2019, 02:15:38 AM
Really nice work! But what is the difference here using this method instead of using one or two LFO's with destination OSC SLOP? Set LFO1 to Triangle and LFO to Random both having OSC SLOP as DESTINATION.

It is explained in a very detailed way in the article that creative spiral wrote and linked to in the first post. To briefly summarise, slop applies a randomised detuning effect whereas the gated sequencer method yields a fixed offset which repeats cyclically. Furthermore it allows precise control of the offsets (of multiple parameters) on up to 16 “virtual voices”. For example, in a 5-virtual-voice setup, keypress 1, 6, 11 etc. will have the same offset values as each other. Keypress 2, 7, 12 etc. will have the same offset as each other. Likewise for the other “voices”.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: panic on March 19, 2019, 08:04:48 AM
Thanks maxter and philroy for the testing!  It confirms what I thought. The trick with the keystep sequencer is still a nice one if you are looking for tuning offsets between your voices (best way to achieve it is programming all the steps of the sequencer, and then do some random playing with more than one note at once), it just doesn’t go as far as creativespiral had hoped in mimicking certain behaviors as voice count or predictability of results.
In the past, to create minimal random offsets between the voices and liven things up, I used to assign very slow keysynced random LFOs in minimal amounts to various destinations. I was really glad with the effects. Until someone on the forum said it was such a shame that the random LFO is not really random, but spits out the same seemingly random pattern every time… I guess my brain was just too willing to hear a result which wasn’t there.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: OakBloodThree on March 19, 2019, 08:34:55 AM
Yes, intonation offsets will be great! I have to try this. I think this plays a major part in the VCO sound, and I'm a big fan of "stretching" the tuning on the upper and lower registers, like on a piano.
Stretching can also be [fairly] easily accomplished with an alternate tuning.  Tunings do not have to have a 2/1 octave. For example, using 19 equal divisions of the tritave (3/1) gives you a perfect twelfth and a slightly stretched octave.

(I have actually been experimenting a bit with regular "squeezed" tunings instead, to make thirds and sevenths "sweeter" at the expense of octaves and fifths.)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 19, 2019, 09:59:50 AM
, it just doesn’t go as far as creativespiral had hoped in mimicking certain behaviors as voice count or predictability of results.

Overall, the voice behavior is very predictable with this modeling..  ie:  if you setup a "virtual voice count" of 5-voices in the gated sequencer, and then play a series of three-note chords, you will get the correct offsets of each voice/note.  (1,2,3) (4,5,1) (2,3,4) (5,1,2) (3,4,5) (1,2,3) etc...  just as you would with a cyclical voice scheme on a real five voice synth.   

The only areas where it doesn't act exactly like real X-voice synth is if you play more than that amount of notes at once, you don't get the voice stealing... which actually isn't necessarily a bad thing.   And as mentioned, some synths like the Jupiter-8 use a voice reset/backtracking scheme.   

But overall I'm very happy with the results... It's a pretty accurate way to model 4-voice, 5-voice, 6-voice or 8-voice vco synths from the past. 

Also, I'm having great results with patch design of other acoustic/analog instruments - Modeling trumpets, flutes, violins, cellos, string ensembles, guitars, pianos, organs, etc.   For these type of real world instruments/ensembles, having unique (and stable) tuning offsets per voice is very realistic.  I'm convinced this is the best approach... everything sounds more organic, and chords have a warmth/richness that can't be achieved with other methods like lfos and slop.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 19, 2019, 10:19:28 AM
Well, had time to do just a little more testing. It does indeed work the way creativespiral intended. If you switch mode and then back, the sequencers get off-set somehow.

Yeah, I've noticed there is an intermittent bug in the gated sequencer / firmware where if you are doing a bunch of step editing / switching between poly and gated seq / changing reset positions around, then some step resets will sometimes get "stuck on"...  I've got to do some more experimentation to lock down the exact repeatable behavior and send a bug report on to SCI... it seems to be very intermittent, but I have run into it a couple times out of fifty or so patches I've setup so far using this method.     

If you power cycle it does fix itself.   And once you have patches saved with the gated seq steps correctly, they do work as intended and have repeatable virtual-voice allocation behavior every time you load them.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Proton on March 19, 2019, 10:32:48 AM
I´ve tested the patches you´ve thankfully sent to me and implemented this concept in some of my patches. you are right: the result is an organic and rich voice behaviour - thanks again - fantastic work !
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 19, 2019, 10:40:59 AM
Really nice work! But what is the difference here using this method instead of using one or two LFO's with destination OSC SLOP? Set LFO1 to Triangle and LFO to Random both having OSC SLOP as DESTINATION.

If you're referring to the VCO Harmonic Jitter modulation experiment:   
I did test out replicating the VCO frequency jitter with Osc Slop Modulation, but was not able to get the same results as measured on the three VCO synths I tested.   The reasons are described in more detail down at the bottom of this thread (https://forum.sequential.com/index.php/topic,3412.0.html)

If you're referring to the Voice Modeling:
The short answer is that randomness and pronounced detuning motion is less realistic than having voice offsets that are more stable.   You may still want some randomness and tuning motion, but that should be secondary to setting up the basic voice offsets first. In the web page I setup, there's a bunch more details and info:  http://www.VoiceComponentModeling.com/vcm.aspx
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: panic on March 19, 2019, 03:22:17 PM
I could open the clip from philroy before, but now that i have seen it, it is clear that you were indeed right on this, and that age is eating my brain away more rappidly than i d hoped. Thanks for sharing, very useful insight for me!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: nanoengguy on March 19, 2019, 06:51:17 PM
I'm a big fan of "stretching" the tuning on the upper and lower registers, like on a piano.

Hi Folks,

I can't really wrap my head around how one would program this, and I'm enthralled by the concept.

Any ideas?

Thanks!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 19, 2019, 07:13:44 PM
I'm a big fan of "stretching" the tuning on the upper and lower registers, like on a piano.

Hi Folks,

I can't really wrap my head around how one would program this, and I'm enthralled by the concept.

Any ideas?

Thanks!

There's two different approaches to changing tuning:
1. If you're going for accurate "Stretched Piano Tuning", your best bet may be to load an Alternate Tuning definition table to the Rev, which sets specific tuning templates to the keys.  Page 71/72 of the Rev2 manual discusses these alternate tunings.   Also, I saw that OakBloodThree just uploaded an updated syx here (https://forum.sequential.com/index.php/topic,3460.0.html), and you might wanna follow that thread.

2. You can use the Mod Matrix to route Note Num to Osc Frequency...  Note Number amount of 128 means that every consecutive key press increases the output by 1.   So if you're routing to Osc Freq, then every consecutive key press will add 1 to Osc Freq (aka +50 cents)... that's on top of Osc Key Tracking and Osc default frequency.    Also, you need to add / account for the first 36 midi notes/keys before you actually get to the first key on the physical Rev2 board.  (in default octave)   So, yeah, using Note Num modulation, you're probably gonna want very low numbers for the amount.   This is the method I'm using for "intonation tuning offsets" with voice modeling... to mimic behaviors I've researched on VCO synths.    Routing even an amount of '1' with Note Number is too much in most cases,.. I'm using gated sequencer (along with two mod slots) to scale down the note number modulation to less than 1.   If you're interested in an example patch, send me your email and I'll send you over some examples of this method...  although, as mentioned, the alt tuning definitions might be more what you want if you're shooting for classic stretched piano tuning. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 31, 2019, 12:51:58 AM
Got my first video up that shows off some voice modeling with the Prophet Rev2: 
Creation of a Giant Brass Pad Sound like the Vangelis Blade Runner Theme.   

https://youtu.be/jB9HG3k3vvQ

I'll be doing some more videos on voice modeling and Rev2 patch creation soon.. I'm working my way through a custom bank of 128 voice modeled patches.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Proton on March 31, 2019, 02:00:12 AM
 perfect !
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Frocktar on March 31, 2019, 08:06:01 PM
Really great work on this mate.

Thanks for the tip!!!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 31, 2019, 08:53:39 PM
Well, had time to do just a little more testing. It does indeed work the way creativespiral intended. If you switch mode and then back, the sequencers get off-set somehow.

Yeah, I've noticed there is an intermittent bug in the gated sequencer / firmware where if you are doing a bunch of step editing / switching between poly and gated seq / changing reset positions around, then some step resets will sometimes get "stuck on"...  I've got to do some more experimentation to lock down the exact repeatable behavior and send a bug report on to SCI... it seems to be very intermittent, but I have run into it a couple times out of fifty or so patches I've setup so far using this method.     

If you power cycle it does fix itself.   And once you have patches saved with the gated seq steps correctly, they do work as intended and have repeatable virtual-voice allocation behavior every time you load them.

Just to update this item... I did track down two minor bugs with the Gated Sequencer / Key Step mode... they have both been reported last week to SCI and confirmed... hopefully they'll be fixed soon, in next OS update.   So if you're trying out voice modeling right now, be aware:

1. When stacking two layers, with both using the Key Stepped Gated Sequencer, the sequencers don't currently keep track of the correct step.. they skip alternating steps.  You still get the the voice modeled sound, but if you were trying to model an 8-voice virtual synth, it will actually just use four of the steps you defined.   (In this patch I created for the Blade Runner sound, that is the case...  It still sounds good with the skipped steps, but once the bug is fixed it will sound even more realistic... IE: more like an 8-Voice CS-80. )   So, not a deal breaker, but something you might notice if you're playing around with stacked, voice modeled layers in OS 1.1.5.9.  (this isn't an issue in single layer programs)

2. There is another weird bug where if you set a Gated Seq Reset, then turn it back to a normal step and set a Reset on another step in the track, the reset positions may not be correct...  So when editing, try and be careful to set your resets on the right step the first time...   Alternatively, if you're moving reset positions around, just save the patch regularly.  For some reason, the act of saving the patch corrects the bug (must be something in a sort of temporary buffer).  So this one is just an editing inconvenience... once patches are saved, they act as intended.

Anyways, just thought I'd mention those so if ya'all are experimenting with this technique, you don't get frustrated with weird results.  Hopefully will be all fixed up soon... and stacked, voice-modeled patches will sound even more organic. 

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: minor7th on April 02, 2019, 11:41:50 AM
Brilliant and very inspirational! I reprogrammed one of my soft analouge pads replacing osc slop and LFO modulations with gated sequence values and boy does it sound much better! Thank you for sharing your ideas :)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: jurfin on April 22, 2019, 09:05:52 AM
Thank you so much for your hard work on this, I made some patches with your techniques and they are absolutely awesome. After doing some testing and comparisons, I have to agree that your method is superior to using slop to recreate subtle differences between voices.

I really appreciate your thoroughness and attention to detail. I’m also incredibly impressed with the creativity behind your approach. It’s such a reasonable solution, I’m annoyed I didn’t think of it first haha!

Would you be opposed to me sharing your site with the tips and tricks threads I’ve made both on this forum and on Gearslutz? It would be a great addition to each of them if you’re alright with me spreading the good news.

Thank you again man, this is really high quality work.




I found a way to better capture the character of classic VCO analog poly synths with the Prophet Rev2.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: OneLittleFonzie on April 22, 2019, 10:51:49 AM
Got my first video up that shows off some voice modeling with the Prophet Rev2: 
Creation of a Giant Brass Pad Sound like the Vangelis Blade Runner Theme.   

I'll be doing some more videos on voice modeling and Rev2 patch creation soon.. I'm working my way through a custom bank of 128 voice modeled patches.

That was really impressing. Not only for Vangelis style big sounds (which I'm not a huge fane of) bit also for other sounds that could use a bit more life. I wouldn't mind getting the patch. But I could make a base patch and use it as template for new patches. I'm not really into saving patches but this could be a nice new basic patch.

Thank you!!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on April 22, 2019, 11:15:09 AM
Hey Jurfin - thanks!   yes, feel free to spread the word about these methods / share links.   

I got a chance last week to visit a local L.A. synth repair/rental shop and take recordings of several classic synths - to investigate voice variance and harmonic jitter.   

I took recordings from a Prophet 5, Prophet 10, MemoryMoog, Korg PolySix, Yamaha CS-80, Oberheim OBX, Oberheim OBXA, Oberheim SEM, plus a Roland Jupiter 4 and Jupiter 8.   I'm gonna do some in-depth analysis, and provide some more details on my findings soon.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: psionic11 on April 22, 2019, 12:39:48 PM
During your analysis, I imagine your main focus will be on pitch variations.  Vintage synths also varied in envelope response -- exponential vs linear vs logarithmic stages for attack and decay.  Do you think it worthwhile to explore these as well?
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on April 23, 2019, 10:45:32 AM
PM'd you with some example patches, OneLittleFonzie.

During your analysis, I imagine your main focus will be on pitch variations.  Vintage synths also varied in envelope response -- exponential vs linear vs logarithmic stages for attack and decay.  Do you think it worthwhile to explore these as well?

Yeah, I'm mostly focused on voice-by-voice pitch variance and harmonic jitter analysis.  I agree that envelope variance is definitely present in classic synths...  Envelope timing (Attack, Decay) is one of the behaviors I've been modeling into most of my voice-modeled patches (like in Blade Runner example video).    It's especially noticeable in patches with pronounced cutoff sweeps... I made a "Tom Sawyer"-like patch that uses two stacked layers with envelope variance... it sounds massive and very organic.    Envelope shape is another topic (ie: concave, linear, convex) that is also worth investigating... but beyond what I'm working on for now.  Maybe next round.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Pym on May 02, 2019, 02:32:27 PM
Just FYI, I have explored this concept quite extensively from many perspectives and I already have most of the code figured out for future products but it isn’t easy to port back due to design choices. I’ve always been fascinated by chaos theory and how to both bound and seed randomness in a way that emulates the part of analog we all love

I may even have some tricks up my sleeve you haven’t thought of yet... stay tuned  ;)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on May 02, 2019, 03:39:51 PM
Just FYI, I have explored this concept quite extensively from many perspectives and I already have most of the code figured out for future products but it isn’t easy to port back due to design choices. I’ve always been fascinated by chaos theory and how to both bound and seed randomness in a way that emulates the part of analog we all love

I may even have some tricks up my sleeve you haven’t thought of yet... stay tuned  ;)

Awesome, Chris!   I'm excited to see your sleeves!   This method of defining per-voice variance with a sort of "lookup table" definitely adds some classic analog realism over random slop and more artificial detuning motion.   The key is having fairly stable tuning per voice / per oscillator, but with unique offsets for each.   And tackling other parameters in the VCO, VCF and VCA sections with per-voice offsets can really create unique analog character. 

I went out a few weeks ago and captured samples of a bunch of synths and I have data tables of voice-by-voice tuning offsets for MemoryMoog, OBX, OBXA, OB SEM, CS80, Korg PolySix, Jupiter 4, Jupiter 8, Prophet 5 and Prophet 10... if you're interested.   I will say, the predominant characteristic is that all of them have these tuning offsets, and most have significant intonation variance up and down the keyboard.. I've been playing with note number modulater to replicate it.

The handling of voice-allocation would be a good area to develop further, as there are a few distinct variants (round robin, reset to voice one, backtracking voice allocation, per key voice allocation, etc..)   Currently the round robin approach is the only one available through the Rev2 modulation. 
 
It's a testament to the design of the Rev2 that it works so well even with current implementation...  but yeah, if we just had "another instance" of the gated sequencer dedicated to being a lookup table for this type of per-voice modulation offsets, I think it will be a really interesting feature on a future board.   If it had a few more lanes of data (6 or 8 lanes), and ability to capture the different voice allocation schemes, that would be awesome!   

Also, I was thinking it would be gravy if the lookup tables could be saved independent of presets... so you could just have prebuilt voice templates for a variety of different classic synths, along with variants of each where they have less-or-more voice character.   Then you could load a patch, or an INIT patch, and then navigate through a list of voice modeled presets (Voice Modeling OFF | MemoryMoog Prime | MemoryMoog Hot and Humid | Prophet 5 | etc...... )

At the bottom of the VoiceComponentModeling.com web article, in Section 5, I outlined a bunch of "future wish list" items.
http://www.voicecomponentmodeling.com/vcm.aspx 

Excited to see what comes next!

Cheers! - Jason
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: shiihs on May 03, 2019, 11:54:01 PM
(seems like voicecomponentmodeling.com is down at the moment)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Pym on May 05, 2019, 11:16:39 PM
Yeah a lot of those ideas are in my notes to one degree or another. Once I end up exploring it more again I’ll try and communicate the process here. I’ll read through your site later this week and check out some of the specifics, sounds like you put a lot of effort into the exploration and we definitely went down very similar paths!

I’m exploring a one knob ‘seeded’ randomness per voice where it controls the range of each parameter that is then changed using the single slop knob. So maybe tuning is 0-+6 cents, vca attack is -1-+2 or whatever. But it starts at 0 for all voices. As you turn up the slop it moves them up to those values, scaling. The beauty being if you select the same random seed (maybe 0-127 or something) you can reproduce the slop behavior, and each voice number modified the seed the same way, so each voice is different but can be recalled with that seed value

Although I see the value given in full control over the offsets, this feels a little more random and ‘analog’ to me, but repeatable since you can save and recall the slop offsets

Just one of the ideas I had related to the topic

Just FYI, I have explored this concept quite extensively from many perspectives and I already have most of the code figured out for future products but it isn’t easy to port back due to design choices. I’ve always been fascinated by chaos theory and how to both bound and seed randomness in a way that emulates the part of analog we all love

I may even have some tricks up my sleeve you haven’t thought of yet... stay tuned  ;)

Awesome, Chris!   I'm excited to see your sleeves!   This method of defining per-voice variance with a sort of "lookup table" definitely adds some classic analog realism over random slop and more artificial detuning motion.   The key is having fairly stable tuning per voice / per oscillator, but with unique offsets for each.   And tackling other parameters in the VCO, VCF and VCA sections with per-voice offsets can really create unique analog character. 

I went out a few weeks ago and captured samples of a bunch of synths and I have data tables of voice-by-voice tuning offsets for MemoryMoog, OBX, OBXA, OB SEM, CS80, Korg PolySix, Jupiter 4, Jupiter 8, Prophet 5 and Prophet 10... if you're interested.   I will say, the predominant characteristic is that all of them have these tuning offsets, and most have significant intonation variance up and down the keyboard.. I've been playing with note number modulater to replicate it.

The handling of voice-allocation would be a good area to develop further, as there are a few distinct variants (round robin, reset to voice one, backtracking voice allocation, per key voice allocation, etc..)   Currently the round robin approach is the only one available through the Rev2 modulation. 
 
It's a testament to the design of the Rev2 that it works so well even with current implementation...  but yeah, if we just had "another instance" of the gated sequencer dedicated to being a lookup table for this type of per-voice modulation offsets, I think it will be a really interesting feature on a future board.   If it had a few more lanes of data (6 or 8 lanes), and ability to capture the different voice allocation schemes, that would be awesome!   

Also, I was thinking it would be gravy if the lookup tables could be saved independent of presets... so you could just have prebuilt voice templates for a variety of different classic synths, along with variants of each where they have less-or-more voice character.   Then you could load a patch, or an INIT patch, and then navigate through a list of voice modeled presets (Voice Modeling OFF | MemoryMoog Prime | MemoryMoog Hot and Humid | Prophet 5 | etc...... )

At the bottom of the VoiceComponentModeling.com web article, in Section 5, I outlined a bunch of "future wish list" items.
http://www.voicecomponentmodeling.com/vcm.aspx 

Excited to see what comes next!

Cheers! - Jason
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on May 08, 2019, 05:41:00 PM
I've been thinking about this a lot...   I would keep the general model of the Gated Sequencer as a Voice Lookup Table:  (over a more flat table of values to all defined attributes)    Although, the idea of having a dedicated potentiometer/interface on the front of the synth to quickly toggle through saved voice templates would be totally awesome! 

Reasons why keeping the gated sequencer / lookup table paradigm is good:

1. You've already got the majority of the programming infrastructure built for it, and its a perfect setup for voice modeling.  The ideal solution may just be to create "another instance" of the gated sequencer lookup table, dedicated to voice modeling, with savable templates.   You can copy a lot of existing IP / code blocks for the gated sequencer implementation, and just make adjustments/upgrades as you see fit. 

2. The gated sequencer type of lookup table is VERY FLEXIBLE for voice modeling- Every type of classic synthesizer, or acoustic/analog ensemble that you are modeling will have different aspects to their voice-by-voice variations.   It's important to be able to address each modeled instrument differently.   ie:  some will have large variance of osc tuning per voice, while others will have very little or none, or tuning may be based on intonation vs static voice based.   

Some instruments may require more pronounced variance to attack/delay/release speeds, or only certain stages of envelope speeds.   Some will require addressing totally different characteristics of VCO, VCF, VCA sections, while leaving other ones alone.   Having ability to control each parameter independently is key if you really want to be able to capture the sound of specific classic synths, or ensembles of real world acoustic instrument sounds.   It's not a one-size-fits-all type of scenario, and the gated sequencer / lookup table model allows you to more precisely model classic synths and real world ensembles.

3. Advanced macro-type controls for voice modeling:  The gated sequencer paradigm for voice modeling also allows you to control more advanced behaviors on a voice-by-voice basis.   For instance, you might build a macro type behavior that uses a note number modulator, routed to Env 3 amount, and the overall amount of note number is controlled by a lane in the gated sequencer, giving voice by voice variance to an "Oscillator Pitch Settle" type of behavior that requires multiple modulations.   I have done this type of voice specific modeling in several patches I've built. 

4. The Gated Sequencer lookup table model also allows you to define a virtual voice count within the synthesizer... by setting a reset at step 7, you can create a virtual six-voice synth, with repeating patterns of voice imperfection.   This is very realistic if you wanted to model a classic synth from the past with a specific voice count that cycles.   You can create any number of "virtual voices" in this manner, to replicate any synth from the past, or specific ensemble sizes for voice offsets.

Below, I've mocked up a hypothetical Voice Modeling table... most of the functionality has already been developed by you guys.  The idea would be to just create "another instance" of the gated sequencer that is dedicated to allowing you to assign a voice model to a given patch... and adding some additional features to optimize it for voice-by-voice modeling. 

a. change data range:   use -62 to +62, instead of 0-125 ... works better to have 0 as a centerpoint with negative and positive offsets.

b. add a few new seq modes:   (Key Step, Reset to 1), (Key Step, Backtrack), (Assigned Key Allocation) -- this will allow you to capture other voice allocation schemes besides round robin, so you can accurately model old Prophets, Jupiters or other synths that use different voice allocation schemes..  Also, this will allow for more accurate voice modeling of real world ensembles (string sections with a principal/lead player)

c. add the ability to save the voice modeling templates / presets...  a hypothetical new board might ship with 64 factory defined voice models or something, but let users add their own user voice models if they want, or make adjustments and save them.   Would allow players to easily take a preset, or Init patch, and select a voice model scheme and build a patch from it.   If you had a dedicated knob like you were saying, you could quickly and easily scroll through voice models.   Once you save a patch, it saves the voice model with the patch.

d. maybe add a couple more lanes (six or eight) for data.   Note, even if this was not implemented as a separate instance of the gated sequencer, you could just build out the feature set on the gated seq, and add a couple extra lanes there. 

Below are some visual mockups:
Shown in the context of the Soundtower Editor style, as its a good visual representation of the capabilities of the gated sequencer paradigm.

(http://www.voicecomponentmodeling.com/images/rev2-voice-modeling-gated-sequencer-with-notes.jpg)


Here's a mockup of opening a window of Saved Voice Model Templates:
A potential future board might ship with 64 factory templates of various voice models for classic synths and acoustic ensemble types.

(http://www.voicecomponentmodeling.com/images/rev2-voice-modeling-gated-sequencer-with-saved-templates.jpg)

Also, added this to Section 5 of the VoiceComponentModeling.com website:
http://www.voicecomponentmodeling.com (http://www.voicecomponentmodeling.com)

btw: thanks shiihs for the note about the site being down... was in process of changing servers. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: psionic11 on May 09, 2019, 08:08:07 AM
Quote from: creativespiral
Some instruments may require more pronounced variance to attack/delay/release speeds, or only certain stages of envelope speeds.   Some will require addressing totally different characteristics of VCO, VCF, VCA sections, while leaving other ones alone.   Having ability to control each parameter independently is key if you really want to be able to capture the sound of specific classic synths, or ensembles of real world acoustic instrument sounds.   It's not a one-size-fits-all type of scenario, and the gated sequencer / lookup table model allows you to more precisely model classic synths and real world ensembles.

Regarding paragraphs 1 and 2 in your post, you did something similar with the free voice-modeled templates you provided a few months ago.  Without the ability to save parts of a program (FX presets, envelope presets, voice-component gated sequencer presets), then just making separate programs, each dedicated to modelling a specific classic synth voice structure, is probably the best approach.

Regarding the quoted part above: 

As you've hinted at, there are various specific characteristics of a signature sound that determine its uniqueness.  A classic synth's voice count and tuning anomalies is one of those aspects.  Another is the particular curve (exp, log, lin) of each envelope stage, as I've brought up a few times.  Yet another is the pitch envelope -- initial flat attack (10-15ms) is brassy, initial sharp attack (5-10ms) is plucky. 

The Moog One even has an initial "Hold" stage, which is pre-attack.  Apparently, in their analysis of various classics, some keyboards have envelopes that fully open for the few ms or so before the rest of the ADSR stages even kick in.  They recommend setting this to around 10ms for emulating the "bite" some synths have.

And I want to mention phase.  Humans are binaural, and use very slight phase differentiations in arriving sounds to locate the sounds in 3d space.  Essentially a single point source of sound is reflected or refracted or received multiple times, and therefore split and time-delayed, resulting in phase differences when re-combined.  With synthesis and sound processing, modern electronic music has co-opted these naturally occurring phenomena, and so we have stereo panning, doppler effect, flanging, chorus, reverb, Leslie rotors, and a multitude of other time-based effects.

The Rev2 has positive contributions such as Pan Spread, Pitch envelopes via mods, limited envelope curve modulation, and of course its built-in FX.  The Rev2 also has a negative contribution with its single knob OSC mixer; there is some kind of phase cancellation going on as the knob approaches noon.  This is why I often choose to use only one oscillator, in order to avoid this weakening and the resulting generic-ifying result when using 2 OSCs.

How this is all relevant to your pursuits with the gated sequencer:

Almost all aspects of the characteristics I've described above have to do with the initial attack of the sound.  That's right... Initial Attack determines an overwhelming part of the timbre or unique characteristic of a sound.  And those milliseconds in the beginning, whether it's pitch or volume or phase, are a very significant part of what we register as unique, and therefore to what to devote more brain processing power, in order to identify, predict, and categorize these aural perceptions.  This is why we can tell a contrived performance using a perfectly sampled violin sound is fake, because of the lack minutiae of changing attack qualities between notes found in a live violin performance -- legato vs staccato vs accent vs vibrato, etc.

In a nutshell, one could use the stepped, gated sequencer to capture and modulate these characteristics - pitch envelope as well per voice pitch variance, envelope curve modulation, OSC waveshape.  At least in theory.

(I blame caffeine for the rant.  I should have used the morning brain power for network engineering study, but hey, I'm on holiday..)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on May 09, 2019, 10:07:19 AM
The Moog One even has an initial "Hold" stage, which is pre-attack.  Apparently, in their analysis of various classics, some keyboards have envelopes that fully open for the few ms or so before the rest of the ADSR stages even kick in.  They recommend setting this to around 10ms for emulating the "bite" some synths have.
Yeah, a Hold Stage would be a nice addition for a future synth (in between Attack and Decay)... Rev2 has Pre-Attack Delay, which is nice for more evolving sounds... but I'd love to see the Hold stage added as well, or shapeable Attack/Decay curves can approximate the same.

Re: Binaural.... The Rev2 has positive contributions such as Pan Spread, Pitch envelopes via mods, limited envelope curve modulation, and of course its built-in FX.  The Rev2 also has a negative contribution with its single knob OSC mixer; there is some kind of phase cancellation going on as the knob approaches noon.  This is why I often choose to use only one oscillator, in order to avoid this weakening and the resulting generic-ifying result when using 2 OSCs.

It think it's not so much phase cancellation, but a factor of the way the Osc Mixer reduces volume of each osc...  I have wondered about this before.. whether the OscMixer could be adjusted to keep volume a bit higher when mixed 50/50 (adjust the curve of the mix).   Would be nice if the perceived volume stayed the same throughout the swing of the mix knob.  Not sure if the current chips can do that?

On a more general note, in regards to binaural/stereo capabilities... the fact that the Rev2 is bi-timbral really opens up so many possibilities.   In fact, I use the second layer to create stereo patches as much or more than creating classic multi-timbral stacks.  The Rev2 is capable of delivering a wide, detailed stereo field by stacking two almost-identical layers with Fixed Pan, either fully L/R layers, or a mix... you can also modulate pan spread in stereo stacks for further binaural goodness.   I've also played around with a few variations of the Leslie effect using dual layers... I have a couple patches in the bank I'm working on where I'm pseudo modeling the horn and drum speeds independently, using dual layers.   

Almost all aspects of the characteristics I've described above have to do with the initial attack of the sound.  That's right... Initial Attack determines an overwhelming part of the timbre or unique characteristic of a sound.  And those milliseconds in the beginning, whether it's pitch or volume or phase, are a very significant part of what we register as unique, and therefore to what to devote more brain processing power, in order to identify, predict, and categorize these aural perceptions.  This is why we can tell a contrived performance using a perfectly sampled violin sound is fake, because of the lack minutiae of changing attack qualities between notes found in a live violin performance -- legato vs staccato vs accent vs vibrato, etc.

In a nutshell, one could use the stepped, gated sequencer to capture and modulate these characteristics - pitch envelope as well per voice pitch variance, envelope curve modulation, OSC waveshape.  At least in theory.

I totally agree that the Initial Attack / Transient Shaping is one of the most important aspects of modeling classic synths, as well as acoustic analog instruments.   That was what I was describing in terms of more macro-type behavior modeling using Env3. 

I was able to capture measurements from a bunch of classic synths and most of them have "oscillator pitch settle" on a per voice basis.. (where there is a subtle transient effect or more pronounced pitch shift right at the beginning of the attack phase) -- its one of the characteristics I've modeled into many of the patches in the bank I'm working on... the nice thing about having a flexible voice modeling table (like the gated seq paradigm), is that you can have it varied on a voice by voice basis... the amount of these effects are not the same for each voice, and will have variance.   

I use Env3 for modeling these type of transient effects or pitch settle effects... Targeting fine tune osc pitch, filter audio mod, recursive shaping, noise mix level, osc shape, and sometimes other characteristics, depending on what instrument I'm modeling... and then control the Env3 amount through a lane in the gated sequencer (voice modeling table), sometimes scaled through mod matrix or sub modulated by note num... which gives each voice some slight variation to its transient phase.   

Also, in regards to real world instruments:  when modeling a ensemble of violins, every "player" in that virtual ensemble will have slight differences in their attack with the bow (attack speed and transient effects), the decay time, the vibrato amount, etc...   All of these aspects can be captured with a voice modeling table... resulting in much more authentic, rich sounds, especially noticeable when playing chords.

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: psionic11 on May 10, 2019, 03:56:06 PM
Yes, there are a lot of pratical uses for gated sequence modulation of attack characteristics.

It's like the injected variation in Voice Component Modeling is the antidote to the static and precise nature of DCOs and digital envelopes.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Gerry Havinga on May 12, 2019, 12:02:44 PM
Well VCM is definitely working for me, created a first patch for the Rev2. The depth and massiveness is really nice. My first try is here (Rev2 is bass), Prophet X plays Mellotron patch:

https://soundcloud.com/user-252754541/live011-mellotron (https://soundcloud.com/user-252754541/live011-mellotron)

Thanks creativespiral, awesome research and really smart thinking  ;) ;)
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on May 13, 2019, 10:42:54 AM
Well VCM is definitely working for me, created a first patch for the Rev2. The depth and massiveness is really nice. My first try is here (Rev2 is bass), Prophet X plays Mellotron patch:

https://soundcloud.com/user-252754541/live011-mellotron (https://soundcloud.com/user-252754541/live011-mellotron)

Thanks creativespiral, awesome research and really smart thinking  ;) ;)

Thanks Gerry.

Nice track!.. Cranked it up and was transported to some deep space exploration :)   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Naboo on May 23, 2019, 01:06:01 AM
Thanks @creativespiral for sharing the knowledge.  One of the first things I do when creating a patch (on any synth) is to add random Lfo to pitch.  I haven’t been enjoying the slop on the rev2, ob6 and As-1 as much as I expected.  Reading this info and listening to some audio, I think this will be hitting that sweet spot I was looking for. Look forward to trying this out!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: SporeSynths on June 03, 2019, 03:40:40 PM
Really interesting information here. Read through the article and watched the videos. Can't wait to try this out on my Rev2.

One thing I'm wondering, and maybe you've explained this and I missed it. In the video you show how your modulation method makes the upper harmonics jitter more like they do on the VCO synths. But why is it that the fundamental doesn't jitter at all with this method, since you are modulating the frequency. Is it just that the amount that you're modulating is so small that it effects the upper harmonics first before effecting the fundamental if the value was increased?
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on June 27, 2019, 11:54:16 AM
Hey SporeSynths - sorry for the delay on response.  In the VCO harmonic jitter tests (separate discussion from Voice Modeling topic), the fundamental does experience the frequency modulation, its just that the amount is very small (ie: usually less than one cent swing, sometimes a bit higher).    That swing in the fundamental seems to have a larger downstream effect on the harmonic series though.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on June 27, 2019, 12:03:00 PM
The Voice Component Modeled (VCM) patch bank for Prophet Rev2 is now available!.. been working on this for the past six months.   128 new patches with lots of classic analog synth sounds, acoustic instrument models, VCM templates and more.   

Here's a video with some short demos of about twenty of the patches:

https://www.youtube.com/watch?v=WleQ2KrN8HY


More Info on VCM
You can read up more on Voice Component Modeling topic on:
http://www.VoiceComponentModeling.com (http://www.VoiceComponentModeling.com)

Some Free Examples
I uploaded some free example patches on:
https://www.PresetPatch.com/user/CreativeSpiral (https://www.PresetPatch.com/user/CreativeSpiral)

Purchasing
If you'd like to purchase the patch bank, it's available here:
https://sellfy.com/sounddesign/ (https://sellfy.com/sounddesign/)


- Jason
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: ouzoman on June 29, 2019, 07:58:55 AM
Great set of patches!  Congrats!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Gerry Havinga on June 29, 2019, 09:40:17 AM
Completely blown away by @creativespiral's patches. Beautiful lush sounding, very organic and massive. The VCM technique really works best with chords and layering A+B, I will have to invest in the 8 voice upgrade and getting my Rev2 up to full strength   :)

@creativespiral if you are ever in the Netherlands, I do owe you a meal and a beer, thanks!

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: gernotreininger on June 29, 2019, 10:07:55 PM
Hi creativespiral. I just purchased your great set of patches. You did a fantastic job and I guess a can learn a lot from your work. Thank you for your creativity and keep on your awesome work.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on July 02, 2019, 03:14:14 PM
@ouzoman, @gerno, @gerry 

Wow...  Thanks guys!!  Appreciate the feedback.   

btw, if you don't already have an expression pedal, I highly recommend picking one up... there are modulation pedal mappings on a lot of the patches...  some have significant morphing of sounds.   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Darrolav on July 04, 2019, 09:24:30 PM
Hi creativespiral  :)
I bought your patches and I have to say that your attempt on vangelis cs80 sound is just amazing :D
Thank you so much for your work
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: gerardplouf on July 05, 2019, 09:25:31 AM
Hello Jason,
Just buy your patches. You make an incredible job.
Thanks for these great soundbank. ;D ;D ;D ;D ;D
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Tugdual on July 06, 2019, 10:33:00 AM
creativespiral you have developped interesting concepts but I believe the real breakthrough would be to access calibration data. I remember the Prophet generating crazy sounds out of calibration, looks like it is far from having delivered all its potential.
Another dream that I have is sequential deciding to share the firmware as an open source.
Somehow Korg started that with their custom generators.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on July 06, 2019, 07:57:53 PM
@geradphouf, @Darrolav - glad you're enjoying the bank - thanks for the feedback guys!  Appreciate it!

@Tugdual - Yeah, the Voice Modeling is basically that type of approach (modeling calibration offsets for tuning, envelope behavior, noise levels, and various other characteristics, on a voice-by-voice basis)   

Once you set up the voice modeling data table in gated sequencer, you can dial in classic analog type intonation tuning offsets (where each oscillator in each voice has increasing or decreasing offsets to tuning, tied to position on the keyboard)... this is the most common behavior I measured in my tests of classic VCO synths (I tested OBX, OBXA, CS80, PolySix, MemoryMoog, Jupiter 4, Jupiter 8, P5v3, P10, and some others)

Or with a little extra adjustment of the data table, you can dial in crazy, de-calibrated old synth character... I've got a couple patches where I push the limits of what sounds good, trying to dial in a sort of classic "MemoryMoog on a hot and humid day" sound, where there's a ton of "de-calibrated" behavior in regards to voice tuning offsets and envelopes.   It works better for certain types of playing/music... If you're playing synth power chords (1,5,8) and octaves you can really push the decalibration, and it can sound really good with lots of classic/organic flavor.   If you're playing more complex passages, then the more dialed back approach works best.   The beauty of it is that once you setup the modulation wiring and lookup table in gated sequencer, all you have to do is swing some values in the seq to make it more wild, or more tamed.

There's some patch examples that you can download for free here if you want to try them out:
https://www.presetpatch.com/user/CreativeSpiral

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Blueskytech on August 07, 2019, 05:01:08 AM
Just purchased your sound bank and in my opinion this is a must have for any Rev2 owner. I also shared your youtube video exploring overtone stability with a couple friends and they all loved. Seriously this is some excellent work and you should keep following whatever path sparks your interest because it is certainly paying dividends.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on August 08, 2019, 02:26:56 PM
Just purchased your sound bank and in my opinion this is a must have for any Rev2 owner. I also shared your youtube video exploring overtone stability with a couple friends and they all loved. Seriously this is some excellent work and you should keep following whatever path sparks your interest because it is certainly paying dividends.

Thanks Bluesky!   Glad you're enjoying the VCM patch bank!   

I'm currently working on a NI Reaktor synth build...  It started as a prototype of voice modeling features I wanted to test, but it has bloomed into a sort of mega-poly-synth... it's a digital version of my dream analog synth, combining favorite features from Poly Evolver, Prophet Rev2, and Moog One.   (16 voice binaural stereo osc routing and amp panning, dual filter setup with flexible routing, analog style core oscillators with shape mod, digital wavetable osc option, expansive voice modeling system, super flexible LFOs, and a ridiculously huge mod matrix with tons of transform options)   Once its finished, I'll post some more info about it.
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: rhullings on August 09, 2019, 02:01:01 PM
I just got this too, it's really great. So many actually useful sounds, for me at least. I've been addicted to the binaural thing for a while and there are lots of those kind of patches, so I'm pretty psyched. Thanks!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on August 11, 2019, 04:32:48 PM
I just got this too, it's really great. So many actually useful sounds, for me at least. I've been addicted to the binaural thing for a while and there are lots of those kind of patches, so I'm pretty psyched. Thanks!

Thanks Rhullings!   Glad you're finding the patches useful. 

Yeah, I'm a big fan of binaural stereo signal paths.   That's one of my favorite aspects of Poly Evolver, and with the bi-timbral capabilities of the Rev2, you can achieve similar results - routing oscillators hard left and right.   

Combined with the Voice Modeling offsets, it can result in a huge/wide stereo field with a ton of definition, or a sort of double-tracked-synth type of sound.   For string and brass ensemble patches, it makes them sound much more like full orchestras. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on August 23, 2019, 10:59:16 PM
This is an example of a Lead patch included in the Voice Component Modeling bank for the Prophet Rev2.

I'm a big progressive rock fan, and Steven Wilson / Porcupine Tree are near the top of my list.   This searing prog rock lead tone is modeled after Adam Holzman's Moog Square Lead from "Regret #9" on the Hand Cannot Erase album.    It uses both layers of the bitimbral Rev2 engine for a wide, binaural stereo image, and has dynamic performance modulation and built in effects.   It also uses voice-modeling to give each voice and each oscillator unique offsets for a more organic, classic analog type of sound.

https://www.youtube.com/watch?v=7Qllu_9l-TI
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: gernotreininger on August 23, 2019, 11:47:47 PM
This is an example of a Lead patch included in the Voice Component Modeling bank for the Prophet Rev2.

I'm a big progressive rock fan, and Steven Wilson / Porcupine Tree are near the top of my list.   This searing prog rock lead tone is modeled after Adam Holzman's Moog Square Lead from "Regret #9" on the Hand Cannot Erase album.    It uses both layers of the bitimbral Rev2 engine for a wide, binaural stereo image, and has dynamic performance modulation and built in effects.   It also uses voice-modeling to give each voice and each oscillator unique offsets for a more organic, classic analog type of sound.

https://www.youtube.com/watch?v=7Qllu_9l-TI
Great. I love Steven Wilson/Porcupine Tree and try to watch Steven everytime he does a show in Vienna. I purchased your bank some weeks ago but didn't have the time to dig deeper but now I have got some extra motivation 🙂
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: guyaguy on January 19, 2020, 05:55:40 PM
I finally spent some time playing around with this. (I had been playing more with mono synths.) This really does make for richer, fuller vintage synth-type sounds. It seems like the filters react differently as well. That may be my imagination but it wouldn't surprise me since there's more harmonic content hitting the filter--sort of like the overtone effects Kevin Shields gets by using vibrato while playing.

The only drawback for me is that it eats up the gated sequencer, which I like using for synced stepped modulation. But there are some workarounds: Use Velocity as Source instead of the Sequencer and route the destination LFO Amount in the Matrix. Since invariably each strike of a key will have slightly different velocity (at least it will with my limited ability!), each note played will vary in its jitter amount.  Of course it won't replicate the modeling effect of the round robining of voices pitched slightly differently. But it will provide enough richness for patches where you want to use the gated sequence for other things like notes, filter cutoff, effects, etc. So I'll probably use 2 Init presets--one for patches I plan to use without other gated sequencer modulation and one for patches in which I plan to use the gated sequencer.

Just for fun I set up a voice model where the 5th note produces no sound to model a Juno 106 with a dead voice chip!  ;D

Thanks again for the work on this and for sharing it, @creativespiral!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on January 27, 2020, 09:36:25 AM
Hey Guyaguy, glad you got a chance to check it out!   Yeah, it definitely does alter the harmonic content hitting the filter section.   Technically, the VCM in the oscillator section results in a bunch of natural phasing that is present in all VCO poly synths, and acoustic ensembles.   If you analyze the combined oscillator output after the osc section, but before the filter, you can see it creates more complex / less sterile waveform with movement, and all of its harmonic peculiarities.

In addition, I've found that applying VCM routings to the Filter Cutoff Destination further creates that sort of classic analog sound, as each voice's filter has slightly different cutoff position...  emulating older/aged VCF chips.  It's very noticeable playing chords with high resonance patches, or binaural stereo layered patches, as each voice/layer will have slight offsets in pronounced cutoff frequencies.  You can also route VCM to filter envelope attack/decay, which produces a similar effect, where the moving cutoff peaks are slightly offset on a voice by voice basis.   Note: the Rev2 does have VCFs, so this does occur naturally to some extent... that's why you have to re-calibrate sometimes...  but if you want to really "virtually age" the Rev2 filter section, its definitely possible by routing directly to cutoff, or to attack/decay/release of the filter.

That's a good workaround to keep access to gated seq with velocity, using the fine tune scaling via mod matrix... although, the effect is extremely pronounced for very soft (ff) and and very strong (pp) strikes, even with using the minimum "1 amount" scaling trick in the matrix and counterbalancing the tuning in the osc section to medium velocity hits (mf/mp)... also, as you mentioned, it doesn't capture the voice rotation aspect.   But, yeah, its a good option to have in the bag of tools!



Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: guyaguy on January 27, 2020, 01:49:24 PM
Hey Guyaguy, glad you got a chance to check it out!   Yeah, it definitely does alter the harmonic content hitting the filter section.   Technically, the VCM in the oscillator section results in a bunch of natural phasing that is present in all VCO poly synths, and acoustic ensembles.   If you analyze the combined oscillator output after the osc section, but before the filter, you can see it creates more complex / less sterile waveform with movement, and all of its harmonic peculiarities.

In addition, I've found that applying VCM routings to the Filter Cutoff Destination further creates that sort of classic analog sound, as each voice's filter has slightly different cutoff position...  emulating older/aged VCF chips.  It's very noticeable playing chords with high resonance patches, or binaural stereo layered patches, as each voice/layer will have slight offsets in pronounced cutoff frequencies.  You can also route VCM to filter envelope attack/decay, which produces a similar effect, where the moving cutoff peaks are slightly offset on a voice by voice basis.   Note: the Rev2 does have VCFs, so this does occur naturally to some extent... that's why you have to re-calibrate sometimes...  but if you want to really "virtually age" the Rev2 filter section, its definitely possible by routing directly to cutoff, or to attack/decay/release of the filter.

That's a good workaround to keep access to gated seq with velocity, using the fine tune scaling via mod matrix... although, the effect is extremely pronounced for very soft (ff) and and very strong (pp) strikes, even with using the minimum "1 amount" scaling trick in the matrix and counterbalancing the tuning in the osc section to medium velocity hits (mf/mp)... also, as you mentioned, it doesn't capture the voice rotation aspect.   But, yeah, its a good option to have in the bag of tools!
The workaround is definitely a "poor man's version"! But the way I have it set up it doesn't make the effect over pronounced (unless desired) but still provides some richness and movement. And it leaves 2 LFOs and the gated sequencer free for modulating the filter, fx, etc. From a standard Init patch it's just routing a triangle LFO 1 to pitch with amount at 1 and a s&h LFO 2 to pitch with amount to 1. In the matrix Velocity is routed to LFO 1 and 2 amount at just 1 or 2. Then LFOs 1 and 2 are routed to shape with values in the negative so it's just not duplicating what the pitch is doing even though it's using the same LFO. Or a looped EG could be used instead if it's free. But the goal was to have a richer oscillator while leaving some LFOs free. It's not as rich as the VCM method but it provides enough movement to make the sound more lively than without it. Since there are more matrix slots than LFOs and EGs I'll probably play around with other variations--Noise to Shape, LFO1 slightly modulating LFO2 time, etc. I also like degradation and warped patches so taking it further can be fun too!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on January 27, 2020, 04:09:58 PM
Oh, I misunderstood what you were doing...  Are you trying to replicate the VCO Jitter Effect, or the Voice Component Modeling

Those are two separate avenues I explored, and both were discussed in this thread.   It sounds like you're replicating the VCO Jitter?   The way you described what you're doing is basically the same:   (ie:  Two LFOs, one triangle, one random, to osc frequency via the mod matrix scaling)

This video explains the VCO Jitter effect: 
https://www.youtube.com/watch?v=Amhl07TVdNM


For clarity, the Voice Component Modeling (VCM) is a separate topic, which has a larger effect.   I tested many classic VCO poly synths (Oberheim SEM4, OBX, OBXA, Prophet 5, Prophet 10, Korg Polysix, Yamaha CS-80, Jupiter 4, Jupiter 8 and other modern VCO synths)  The primary finding I made (besides the VCO jitter), is that each voice on these classic VCO poly synths have unique offsets to Osc Tuning, Filter Behavior, and other characteristics, on a voice-by-voice, and component-by-component basis.   These offsets tend to be stable, per-voice, per-component.

For example, if you measure Voice 1, Oscillator 1 of an OBX or other synth, you'll find that it has a specific tuning temperament that can be mapped across the keyboard.  (the most common osc tuning behavior that I measured is an intonation based tuning offset / osc scaling offset that causes a given voice/osc to be "in tune" at a certain key, but get progressively flatter or sharper as you go up/down the keyboard.  Different synths have different tendencies, and different voice allocation schemes. 

It's important to note that if you keep that oscillator playing, or return to it again, it will have that same offset each time you hit it - the offsets have stability to them.  They do have some high frequency jitter, but that's a different, and less noticeable aspect, at least in terms of polyphonic patches.   The "perceived motion" that is heard when multiple VCO oscillators play together is "natural phasing" that is just a result of stable tuning offsets in juxtaposition with each other.

In contrast, when using Osc Slop, or LFOs, you get an artificial motion on top of that natural motion.  LFOs/Slop artificially warp and swing the tuning of each oscillator, which is an un-realistic motion, if you're trying to get a classic VCO poly sound, or real acoustic ensemble.   On the VCM website, I discuss this topic in further detail.   

Anyways, it sounds like you may be accomplishing a sort of VCO Harmonic Jitter effect, based on how you described the your routing...  I do still use this type of effect on some patches too, as it can "soften up" the harmonics.   But the VCM I use on virtually all patches. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: guyaguy on January 27, 2020, 05:46:59 PM
Oh, I misunderstood what you were doing...  Are you trying to replicate the VCO Jitter Effect, or the Voice Component Modeling
Oh I tried both. VCM is great for playing keys or sequencing externally. But I'm using a simplified version of your jitter effect routing for patches that use the gated sequencer. Then I add velocity to vary the mod amount just to supply some variation.

It actually works out pretty well like that because my patches using the gated seq are pretty modulation heavy and/or have a shorter decay; so the phasing and nuances probably aren't as noticeable as with pads and legato patches. Those I'm more likely to play on the keys anyhow so using the VCM keystep method works out well for that!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: newsynthguy on March 06, 2020, 04:10:41 PM
Are there next steps for you on this Jason?  Any way I can help?  I’m actually pretty shocked at how much of a difference this makes. Kudos, I feel like this discovery should be more widely known!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 06, 2020, 04:56:40 PM
Hey @newsynthguy -

Glad you're enjoying Voice Modeling!   Yeah, I have a few things on the horizon.

#1 - I've got a bunch of video and audio footage from my research phase for this topic - I recorded hundreds of samples from several classic synths:  Oberheim OBX, OBXA, Roland Jupiter 4, Jupiter 8, Prophet 5, Prophet 10, Yamaha CS-80, Korg Polysix, MemoryMoog and several others.   I've been meaning to edit it all together in a video presentation that shows the process I went through, and gives a video overview of Voice Modeling... basically a video version of the website I put together:  http://www.VoiceComponentModeling.com - I think that will probably raise awareness of it.   I'm really hoping that synth designers will implement it in future hardware and digital products.   It greatly helps the sound of digital or DCO based synths, and even synths that are well tamed modern VCO synths could benefit from voice modeling... as it allows you to dial in the character of many classic synths.   It sounds like Sequential may integrate voice modeling into future products.  Chris (Pym) mentioned in this thread that he was working on it.

#2 - I've started working on a new bank of VCM patches for the Rev2...  A sequel to the product I am currently selling https://sellfy.com/p/figZ/    A lot of people have purchased the current VCM bank, and the response has been really great.  Thanks to everyone who has purchased, and thanks for the comments/feedback - it's very encouraging :)   

#3 - I got into Native Instruments Reaktor a few months back, and I've been programming/wiring up a poly synth that I will be releasing, hopefully in the next few months.   It started as a sort of exploration of voice modeling capabilities, but it has evolved into a fully featured digital poly synth with basically all of my favorite features from modern hardware poly synths - it takes a lot of inspiration from Evolver, Moog One, Rev2, and Super6.   ie:  parallel binaural stereo architecture, extensive mod matrix with tons of advanced modulation features, highly visual interface, super flexible LFOs and envelopes, an extensive digital effects section with modulation, and of course a fully featured voice modeling architecture.   I'm calling it "PolyMage".   Once it's complete, I will post about it on this forum and gearslutz.  Here's a preview of the interface in its current state: http://www.polymagesynth.com/

I'm currently going through a house remodel / studio remodel, so I have not been able to get much progress on these items in the past couple months, but now nearing the finish line, so I'll be focused on them.

I could use some beta testers and patch designers soon for the Reaktor PolyMage synth, but would need people who have full versions of NI Reaktor 6. 
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: newsynthguy on March 10, 2020, 04:47:54 AM
1. Amazing.  Looking forward to it.  I really hope hardware synth makers take note, to your point, having a great analog hardware synth with the ability to change the character of it via wavetables feels like a huge breakthrough.

2. Awesome! I already bought the first volume, hopefully you finish the second.  I'd be curious if people would donate to something like this via Patreon, etc.  I definitely would.

3. Doubly awesome.  I'm 100% down to help beta test, etc.  (I own R6).

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on March 18, 2020, 12:05:49 AM
Have been meaning to make a list of patches in the VCM Prophet Rev 2 sound bank... finally got around to it:

1   KEY ResoPluck VCM         Aggressive Resonant Pluck
2   KEY AnalogPluck VCM         Classic Analog Pluck
3   KEY PluckBow VCM         Plucky Bowed Synth
4   KEY XpercPlk VCM         Percussive Pluck
5   KEY BanditPlk VCM         Plucky Stab
6   KEY TemplePluck VCM         Percussive Eastern Pluck
7   KEY MysticPluck VCM         Eastern Pluck Buzz
8   KEY SuperClav VCM         Clavinet Supersticious
9   KEY EP WurLeslie VCM      Electric Piano Wurli with Leslie Speaker
10   KEY EP Rhodes VCM         Electric Piano Fender Rhodes
11   KEY EP PsycPhase VCM      Zeppelin No Quarter
12   KEY EP Everything VCM      Radiohead Everything
13   KEY PizzPluck VCM         Pizzicato Pluck
14   KEY EP Ethereal VCM         Electric Piano Ethereal
15   KEY BellSwirlPad VCM         Bell Key Pad
16   KEY EP Submarine VCM      Underwater Electric Piano
17   SYN VcoSawStab VCM      Classic Lead Saw Stab
18   SYN BrightStabSt VCM      Bright Stab
19   SYN GX1 JPJ Love2 VCM      Zeppelin All My Love
20   SYN MemMoog VCM         Memory Moog Punchy Res
21   SYN FourSawStereo VCM      Four Osc Saw in Stereo
22   SYN WaveChorus VCM      Chorus Synth
23   SYN ProChirp VCM         Wind Chirp Synth
24   SYN HugeSweep VCM         Tom Sawyer Sweep
25   SYN Omega 8V4O VCM      SE Omega Style 4 Osc Emulation
26   SYN Mmoog6V3Saw VCM      Memory Moog Style 3 Osc Saw
27   SYN 8V4O-Mega VCM         4 Oscillator Stack
28   SYN PolySaw OBX VCM      Oberheim OBX Emulation
29   SYN Dark Sector JC         Gated Seq Synth Rhythm
30   SYN ResoStab VCM         Resonant Stab Lead
31   SYN WindVox VCM         Synthetic Wind
32   SYN 80sRhythm VCM         Classic Synth Rhythm
33   BRS DynFlute2 VCM         Dynamic Flute Ensemble
34   BRS DynTrumpet VCM      Dynamic Trumpet Ensemble
35   BRS OBXABrass VCM         Classic OBXA Brass
36   BRS Vangel CS80 VCM      Vangelis CS-80 Style Brass Pad
37   BRS VCO OBX Simp JC      Simple Minds Don't You Forget About Me
38   BRS VCO OB Hybrid JC      OBXA Modified Brass
39   BRS VCOBrassSlow VCM      Classic Analog Brass Pad
40   BRS 80s Classic OB2T         Classic Analog Brass Lead
41   BRS Camera Eye VCM         Rush Camera Eye
42   BRS WideSawBrass VCM      Huge Stereo Brass Ensemble Pad
43   BRS JumpOBX SawPls VCM      Van Halen JUMP
44   BRS AnalogBrass VCM      Classic Analog Brass
45   BRS ClassChorus VCM      Classic Brass Chorus
46   BRS Flanger 2059 VCM      Soundtrack Brass Flange Pad
47   BRS Prophetic VCM         Classic Prophet Brass
48   BRS TrumpetEns VCM         Huge Brass Ensemble Concert Hall
49   STR MegaPWM 2 VCM         Mega Pulse Width Modulation
50   STR Ssaw Detune VCM      Supersaw Detune Emulation
51   STR DynStrings VCM         Dynamic String Ensemble
52   STR Orchestra VCM         Orchestral String Ensemble
53   STR Machine 330 VCM      Classic String Machine
54   STR Subdiv OBX VCM         Rush Subdivisions
55   STR Mmoog Swell VCM      Memory Moog Style Swell
56   STR EmoPhase VCM         Solo String Phased Lead
57   STR WideVCOStr VCM      Huge Stereo Synth Strings
58   STR SlowSomber VCM      Moody Soundtrack Strings
59   STR SmoothExp VCM         Expressive Control String Lead
60   STR DynEnsemble VCM      Huge Soundtrack String Ensemble
61   STR SynthetiPad VCM         80s Synthetic String Pad
62   STR SoloStrings VCM         Fast Attack Strings
63   STR ViolaSawSyn3 VCM      Synthetic Viola Strings
64   STR Prophetic8 VCM         Classic Prophet Synth Strings
65   PAD SolFlare CS8 VCM      CS-80 Piercing Soundtrack Pad
66   PAD Unveil CS8 VCM         CS-80 Brassy Soundtrack Pad
67   PAD Astral Choir VCM         Huge Ethereal Synthetic Choir Pad
68   PAD VCO Prophet 5         Mellow Classic Prophet Pad
69   PAD VCO Hybrid P5 JC      Stereo Prophet Pad
70   PAD VCO P5 PWM JC         Pulse Modulated Brassy Pad
71   PAD VCOPoly8 PWM VCM      Pulse Modulated String Pad
72   PAD Prophet VCF         Mellow Prophetic Pad
73   PAD Discovery 5 VCM         Filter Opening Pad
74   PAD Soft Pad VCM         Subtle Background Pad
75   PAD Discovery 5B VCM      Classic Analog Brassy Pad
76   PAD PulseWind VCM         Bright Brassy Airy Pad
77   PAD SpiritVox VCM         Choir Ensemble Pad
78   PAD ZPField VCM         Zero Point Field Pad
79   PAD ElecCityPWM VCM      Dirty Electric Pad
80   PAD Stargate VCM         Wide Filter Opening Pad
81   BRS Ceremony VCM         Brassy Filter Pad
82   BRS AnalogBrass VCM      Classic Analog Brassy Bass
83   BRS ClassChorus VCM      Classic Chorus Brass
84   BAS MoogySqr VCM         Classic Moog Square Bass
85   BAS MoogyThumb VCM      Percussive Moogy Bass Pluck
86   BAS Minitaur VCM         Buzzy Minitaur Bass
87   BAS ResoSync VCM         Hard Sync Resonant Bass
88   BAS Myxomatos VCM         Radiohead Myxomatosis Bass
89   LED-M PfunkBern VCM      Parliament Funkadelic Flashlight Lead
90   LED-M MoogSync VCM      Moogy Sync Lead
91   LED-M Cosmonaut VCM      Piercing Triangle Space Lead
92   LED-P WindMeth         Poly Lead Airy Wind Lead
93   LED-M BrkFree2 JCC         Queen I Want to Break Free Lead
94   LED-P Scaled Sync JC         Aggressive Sync Lead
95   LED-P PEK Organ ST J      Poly Evolver Pop Organ Lead
96   LED-M Saw4Stack VCM      Huge 4Osc Stack Lead
97   LED-M VCO StereoStac      Aggressive Stereo Stack Lead
98   LED-M VCO Holzman JC      Steven Wilson Regret 9 Lead
99   LED-M LetsGoCars VCM      Cars Lets Go Lead
100   LED-M SqrHolzman VCM      Adam Holzman Lead
101   LED-M Radiant VCM         Radiant Electronic Lead
102   LED-M BrassLead VCM      Aggressive Brassy Lead
103   LED-P WindVox VCM         Soft Poly Air Lead
104   LED-P Prog Organ VCM      Prog Rock Poly Organ Lead
105   LED-P ProphetStab VCM      Prophet Stab Lead
106   BAS Prores VCM                 Prophet Resonant Bass
107   BAS NaturalSlap VCM         Natural Electric Bass
108   BAS Hybrid SH VCM         Hybrid SH Style Bass
109   BAS VoyagerStk VCM         Moog Voyager Stack Bass
110   BAS BodyPunch VCM         Bass with Meaty Tri Sub
111   LED-M FatUnison VCM      Fat Unison Lead
112   BAS AnalogHit VCM         Percussive Bass
113   ORG VCOrgan VCM         Bright Synth Organ
114   ORG PipeOrgan VCM         Huge Atmospheric Pipe Organ
115   ORG Leslie B3 VCM         B3 Style Organ
116   ORG VoxFIre VCM         Doors Light My Fire Organ
117   VCM 4V3O (Int, Jit)         VCM Template 4Voice, 3Osc, Intonation)
118   VCM 6V2O (FFJG)         VCM Template 6Voice, 2Osc, Per Voice)
119   VCM 6V3O (Int)                 VCM Template 6Voice, 3Osc, Intonation)
120   VCM 5V2O (Int, Jit)         VCM Template 5Voice, 2Osc, Intonation)
121   VCM 8V2O (IIJG)         VCM Template 8Voice, 2Osc, Intonation)
122   STR StacattoStr VCM         Staccato String Plucks
123   BRS Ceremony VCM         Soundtrack Brass Bright Pad
124   BRS SlowJump VCM         Soundtrack Brass Buzzy Pad
125   STR Hybrid Pluck VCM      Hybrid String Pluck
126   PAD ColdFire VCM         Percussive Soundtrack Pad
127   STR PWMStab VCM         Pulse Modulated String Stab
128   VOX Humana Pmoog VCM      PolyMoog Vox Humana Gary Numan Cars
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: newsynthguy on April 07, 2020, 10:44:03 AM
Is there a way to simulate VCM inside Omnisphere 2?
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Jason on July 30, 2020, 03:19:05 PM
I posted something like this on another thread and wanted to put it here too:

Back in December I started reading about the VCM techniques developed by Creativespiral and bought his patches. I just love what he has done! It's so clever, and it definitely gives me a lot more of the vintage feel than I ever had before. Another technique he uses a lot is hard panning, which is easy to do on the Rev2. (Quite often, I have an individual patch hard panned via the stacked layers... and then I also pan again with my Rev2 module as I learned from Sacred Synthesis, which of course gives even more richness and depth.) I find the results with all the panning combined with Creativespiral's techniques more satisfying than anything I did before. I started using Jason's templates to rework patches, and have done a lot of programming over the last several months. I borrowed a friend's KingKorg, which is digital but has a lot of well programmed classic patches and used it along with Jason's templates to come up with some of my favorite Rev2 patches. There is simply no comparison between the results that I'm getting now compared to when I was using the '08's. I have never been happier with my sounds!

I hope you continue to work on a second set.

Best Regards.
- (also) Jason
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on August 01, 2020, 08:47:04 AM
Back in December I started reading about the VCM techniques developed by Creativespiral and bought his patches. I just love what he has done! It's so clever, and it definitely gives me a lot more of the vintage feel than I ever had before. Another technique he uses a lot is hard panning, which is easy to do on the Rev2. (Quite often, I have an individual patch hard panned via the stacked layers... and then I also pan again with my Rev2 module as I learned from Sacred Synthesis, which of course gives even more richness and depth.) I find the results with all the panning combined with Creativespiral's techniques more satisfying than anything I did before. I started using Jason's templates to rework patches, and have done a lot of programming over the last several months. I borrowed a friend's KingKorg, which is digital but has a lot of well programmed classic patches and used it along with Jason's templates to come up with some of my favorite Rev2 patches. There is simply no comparison between the results that I'm getting now compared to when I was using the '08's. I have never been happier with my sounds!

I hope you continue to work on a second set.

Best Regards.
- (also) Jason

Hey Jason - thanks for the kind words / review!   Happy to hear you're enjoying the soundset and using VCM techniques on your patches.   It definitely gives the Rev2 a ton of classic synth or acoustic ensemble character.   DCOs in their natural state are just a bit too perfect. Using Slop produces a somewhat passable, but highly artificial sounding drift/motion.   Individual voice modeling just makes each voice sound "right"...  Like classic VCO poly synths, or like individual players/voices in an orchestra with slight variance to their instrument tunings of a couple cents each.

I am working on a new bank of VCM patches... have just been bouncing between patch creation on Rev2, Deepmind and Pro3, so progress has not been super fast.  And family / young daughters are a constant distraction. 

Anyways, looking forward to hearing more of your music soon!  Cheers, Jason
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on October 01, 2020, 07:46:28 PM
Yeah a lot of those ideas are in my notes to one degree or another. Once I end up exploring it more again I’ll try and communicate the process here. I’ll read through your site later this week and check out some of the specifics, sounds like you put a lot of effort into the exploration and we definitely went down very similar paths!

I’m exploring a one knob ‘seeded’ randomness per voice where it controls the range of each parameter that is then changed using the single slop knob. So maybe tuning is 0-+6 cents, vca attack is -1-+2 or whatever. But it starts at 0 for all voices. As you turn up the slop it moves them up to those values, scaling. The beauty being if you select the same random seed (maybe 0-127 or something) you can reproduce the slop behavior, and each voice number modified the seed the same way, so each voice is different but can be recalled with that seed value

Although I see the value given in full control over the offsets, this feels a little more random and ‘analog’ to me, but repeatable since you can save and recall the slop offsets

Just one of the ideas I had related to the topic

Awesome, Chris!   I'm excited to see what's up your sleeves!   This method of defining per-voice variance with a sort of "lookup table" definitely adds some classic analog realism over random slop and more artificial detuning motion.   The key is having fairly stable tuning per voice / per oscillator, but with unique offsets for each.   And tackling other parameters in the VCO, VCF and VCA sections with per-voice offsets can really create unique analog character. 

I went out a few weeks ago and captured samples of a bunch of synths and I have data tables of voice-by-voice tuning offsets for MemoryMoog, OBX, OBXA, OB SEM, CS80, Korg PolySix, Jupiter 4, Jupiter 8, Prophet 5 and Prophet 10... if you're interested.   I will say, the predominant characteristic is that all of them have these tuning offsets, and most have significant intonation variance up and down the keyboard.. I've been playing with note number modulater to replicate it.

The handling of voice-allocation would be a good area to develop further, as there are a few distinct variants (round robin, reset to voice one, backtracking voice allocation, per key voice allocation, etc..)   Currently the round robin approach is the only one available through the Rev2 modulation. 
 
It's a testament to the design of the Rev2 that it works so well even with current implementation...  but yeah, if we just had "another instance" of the gated sequencer dedicated to being a lookup table for this type of per-voice modulation offsets, I think it will be a really interesting feature on a future board.   If it had a few more lanes of data (6 or 8 lanes), and ability to capture the different voice allocation schemes, that would be awesome!   

Also, I was thinking it would be gravy if the lookup tables could be saved independent of presets... so you could just have prebuilt voice templates for a variety of different classic synths, along with variants of each where they have less-or-more voice character.   Then you could load a patch, or an INIT patch, and then navigate through a list of voice modeled presets (Voice Modeling OFF | MemoryMoog Prime | MemoryMoog Hot and Humid | Prophet 5 | etc...... )

At the bottom of the VoiceComponentModeling.com web article, in Section 5, I outlined a bunch of "future wish list" items.
http://www.voicecomponentmodeling.com/vcm.aspx 

Excited to see what comes next!

Cheers! - Jason

Nice!...  looks like you got this implemented for New Prophet 5/10, with a single knob macro for offsets...   Congrats on the Rev4!   
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Jason on October 02, 2020, 04:25:20 PM
I would love to hear some comparisons some day!

I wonder if you would give a more detailed run down of your templates some time. For example, do they all have similar amounts of jitter? Would one be better for monophonic patches? What is the difference between patches with different tuning settings (-4 vs. -32 if I remember right). Thanks!
Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on October 03, 2020, 12:17:22 AM
I would love to hear some comparisons some day!

I wonder if you would give a more detailed run down of your templates some time. For example, do they all have similar amounts of jitter? Would one be better for monophonic patches? What is the difference between patches with different tuning settings (-4 vs. -32 if I remember right). Thanks!

I'll try to not turn this into a book... a few notes that are sort of big picture items:

1. Modeling VCO Jitter / Harmonic Jitter with a DCO or digital oscillator -- I usually only use this modeling technique on simpler sound designs... mono basses, leads, and simpler poly sounds.   The effect is subtle - I think it's basically drown out with any sort of more complex patch design with other LFO modulation going on, filter modulation, or lots of oscillators going at once.   It takes 1-2 LFOs to pull off the effect realistically, and to me LFOs are at a premium value for sound design... this decision to ignore the jitter on many patches comes down to not wanting to sacrifice the LFOs and just feeling like in the grand scheme, I don't notice the difference as much for my completed patches.  The audible effect of this is nowhere near as significant as the Per Voice modeling for component values.

2. There's two main approaches to modeling oscillator tuning - either 1. assigning a per voice / per oscillator offset to each, and that offset will be the same up and down the keybed whenever that voice is triggered.   Or 2. multiplexing in a note number modulation slot to give each oscillator an offset, which also includes the intonation / osc scaling tendency over multiple octaves.   In the great majority of synths I tested, the latter approach is what I measured... synths tend to have tuning scaling issues over a five octave range where they will go either flat or sharp progressively as you go up/down the keybed.   Sometimes the tuning varies just 3-8 cents over five octaves on a given voice, and sometimes significantly more.  I tested two MemoryMoogs, and they had particularly bad performance (lots of character) over five octave range (some oscillators having around 15-20 cents variance over that range).   So, for max realism I recommend the intonation/notenum approach most of the time.. In the Rev2, it does take up several mod slots (4-5 total) to do this, whereas the straight voice offsets just use 2 mod slots.   The straight per-voice, per-osc modulation gets you 90% of the way there though in terms of capturing the tuning voice modeling character... but yeah, if you really want top realism, spend the extra two slots to model it with intonation too.   I use both methods.

3. After setting up modeling for Osc1/2 tuning per voice, the next highest priority items for me are usually giving offsets to Env Attack and Env Decay per voice.  If you add just small offsets to these parameters on a per voice basis, you'll capture the slight timing variation that classic envelopes have voice to voice... and the downstream effect is that the filter cutoff point will have temporal offsets from voice to voice, so you're sort of killing two birds with one stone.  This works great for big stacked or unison Sawyer type of filter sweeps.   You can model any number of other parameters with voice modeling too... some patches I directly target filter cutoff per voice - others I will model a macro pitch settle effect at the transient attack and have that vary per voice (this is a common effect of old synths, to have a quick transient pitch settle at the start of each new note).   And there's many other variations that can be targeted per voice, just depending on the specific sound design you're working on.

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Jason on October 03, 2020, 01:35:12 PM
Thanks for the detailed answers!

If I wanted to see if a sound has the jitter effect, what can I look for?
I assume that templates like: #117 VCM 4V3O (Int, Jit) and #120 VCM 5V2O (Int, Jit) have it based on the Jit of the title?

Two of the best Oberheim sounds that I've ever heard on any Sequential gear are:
#40 BRS 80s Classic OB2T (What does the 2T refer to?) and #44 BRS AnalogBrass VCM. (These are especially big given how I am panning two Rev2s Left and Right.)
On these patches, the fine tuning is -31, while the fine tuning of your templates (e.g., 117, 120) is +4...
Subdivisions OBX fine tuning is +21...
SYN GX1 JPJ Love2 fine tuning is -7
Would you please explain why the differences?

Similarly, why does one of the Adam Holzman Leads have a fine tuning of -31, while the other is -2?

Many thanks again,
- Jason

Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: creativespiral on October 03, 2020, 08:59:05 PM
Thanks for the detailed answers!

If I wanted to see if a sound has the jitter effect, what can I look for?
I assume that templates like: #117 VCM 4V3O (Int, Jit) and #120 VCM 5V2O (Int, Jit) have it based on the Jit of the title?

Two of the best Oberheim sounds that I've ever heard on any Sequential gear are:
#40 BRS 80s Classic OB2T (What does the 2T refer to?) and #44 BRS AnalogBrass VCM. (These are especially big given how I am panning two Rev2s Left and Right.)
On these patches, the fine tuning is -31, while the fine tuning of your templates (e.g., 117, 120) is +4...
Subdivisions OBX fine tuning is +21...
SYN GX1 JPJ Love2 fine tuning is -7
Would you please explain why the differences?

Similarly, why does one of the Adam Holzman Leads have a fine tuning of -31, while the other is -2?

Many thanks again,
- Jason

Thanks!  Yes, those templates with "Jit" have jitter in them.   As mentioned, I don't tend to model the jitter in a lot of patches, just because of the multi-LFO requirement to do it accurately and I just don't hear that much of difference in more complex sound designs...  The effect of the Voice Modeling the Tuning Offsets and other Env/Filter characteristics has a much more dramatic effect than Jitter, and that's where I spent most of my time in research and sound design / modeling.   There are a few patches in the soundset that have it modeled with Jitter though.  I used the term "VCO" in the name of a few, to indicate they have VCO jitter modeled...  You can model the jitter with a single triangle LFO to get "in the ball park", or use an additional second random LFO as well to get closer to what I measured in various VCOs... and this can also be modeled per voice as well (and even if not modeling it with separate per-voice values, you still need to use the gated seq and mod matrix to scale down the values to appropriate ranges)   For VCO jitter modeling, I usually use a rate around 54-60 for the LFOs, just based on what I found.


The patches like those two BRS ones you mention, where you see fine tuning as -31 value, are patches that have standard voice tuning offsets to each oscillator (without intonation / osc scaling modeled).  Whenever you hit the associated "virtual voice" based on how many steps you use in the mod sequencer, the offset for that voice/osc will be the same.    The -31 to fine tuning is just an offset so that the voice modeling via the gated/mod sequencer zeroes out the tuning at a value of around +62, which is about the centerpoint of the mod sequencer value range.   It's just a counterbalance, so there's room to tune both flat and sharp per voice in the sequencer/lookup table.   I think the majority of patches I've developed as standard tuning offsets per voice use this '-31' offset value... that became my standard template.

The #54 Subdivisions OBX patch uses the intonation based per-voice offsets (aka osc scaling per voice)...   you'll notice in the mod matrix, there are four slots used for voice modeling (1&2 modulate the amounts of 5&6, which use note-number to achieve oscillator scaling.   For this patch, along with some others, I used measurements I took from an Oberheim OBX synth as references, and tried to get as close as I could to the actual tuning tables I cataloged.   One of the common behaviors I measured in several classic polys is this osc scaling / intonation, and specifically where the oscillators tend to be more sharp in the lower octaves and progressively get more flat as you go up several octaves.  So that was how I did the voice modeling for this patch and some other OB style ones.   In this case, the +21 was required as an offset to make it so that the center of the keybed is mostly in tune for most voices (around C4/C5)  The exact tuning is of course different per voice/per osc, but with this intonation effect modeled.

The GX1 John Paul Jones All of My Love patch uses the per-voice intonation modeling also, but instead of oscillators getting more flat as they progress up the keybed, they are getting progressively sharper.  The smaller '-7' offset to tuning on this patch is just balancing the way that note number is scaled up from C0 on the Rev2.   That value was used to get the keyboard in most nominal tuning in the C2-C4 range for that patch.   The offsets for the intonation based patches just adjust which area of the keybed is "most in tune", which is how classic synths behave..  They usually have an area somewhere between C2 and C5 where they are pretty well in tune, but as you diverge from that sweet spot, things get progressively looser in tuning, and you get a lot more vintage character. 

For the two Adam Holzman Lead patches, the #98 patch was modeled from a patch that I use constantly on my Poly Evolver Keyboard, but added just a bit of voice modeling to it and the VCO jitter modeling... That's one of my favorite lead sounds.  The '-2' offset in that patch was all that was needed, just based on me using less of the range in the mod sequencer... I think that patch was one of the earliest voice modeling tests I did.     The #100 Holzman Lead patch is a more advanced variant on that sound design using stacked, hard panned layers, and my more standard value ranges for regular per voice modeling.



Title: Re: Voice Component Modeling with the Prophet Rev2
Post by: Jason on October 04, 2020, 04:59:11 PM
Thank you so much for such a detailed response! It helps me understand what’s going on be behind the curtain, as your programming skills are on another level. I think the Rev2 would be even more popular if people could hear your patches when they are demoing it.