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Might buy a Rev2, have one question first

Re: Might buy a Rev2, have one question first
« Reply #20 on: August 25, 2020, 03:08:23 PM »
Some of the simple folk do still claim to be able to tell the sonic difference between a DCO and a VCO.

https://youtu.be/b9UxnbGszaY?t=56

I feel that I can tell the difference between a DCO and a VCO at a certain early stage during sound sculpting, but not so much from the pure output produced by the oscillator waveform.  Just listening to a raw saw tooth for example from the OB6, P6, or Rev2, if I asked 1000 participants in an Internet survey to pick out which one was a DCO, I bet the random guesses would be evenly distributed.

However, take those OSCs and do something with them... like set them all to square and modulate the shape slightly for a little PWM, and very quickly you can start picking up the sound profile of each synth, and start identifying which is the Prophet 6 vs the OB-6 vs the Rev2.  I'm still not sure that would indicate which is VCO or DCO if one was not familiar with subtle characteristics of how each synth sounds. 

Vintage Roland Junos were DCO based synths, yet still considered some of the warmest sounding analogs of their time.  Yet, this is not to say all VCOs or DCOs are created equal, or that DCOs and a purely digital oscillator necessarily have the same characteristics.

In referring to "simple folk," I was being sarcastic.
The Musical Synthesizer YouTube Channel:
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The Musical Synthesizer Blog: https://themusicalsynthesizer.wordpress.co

LPF83

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Re: Might buy a Rev2, have one question first
« Reply #21 on: August 25, 2020, 03:18:39 PM »
In referring to "simple folk," I was being sarcastic.

.. I realized that when I saw Nick Batts was hiding behind that URL :)
Prophet 6, OB-6, Prophet Rev2-16, Korg Minilogue XD module, Roland SPD-30, Roland SPD-SX, Roland KT-10, Maschine, Focusrite Scarlett 18i20 3rd Gen + Octopre.

Re: Might buy a Rev2, have one question first
« Reply #22 on: August 26, 2020, 06:24:35 AM »
Ok it should arrive today and I'm currently watching your video about using the gated sequencer to make it sound a bit more not perfectly in tuned between voices.  Didn't realize how much you could do with that, very excited!

maxter

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Re: Might buy a Rev2, have one question first
« Reply #23 on: August 26, 2020, 12:17:05 PM »
Ok it should arrive today and I'm currently watching your video about using the gated sequencer to make it sound a bit more not perfectly in tuned between voices.  Didn't realize how much you could do with that, very excited!

Yep, this actually may beat having just ONE vco-polysynth... because you can mimic different behaviours of various vco-synths, and you're not stuck with one characteristic. You're not bound to a particular one all the time, and if you need perfectly tuned oscillators, you've got that too. Let's just hope that Sequential implement osc finetune as a mod destination, so we don't have to sacrifice unnecessarily many mod slots in the mod matrix to achieve this, if so we can have some more slots left to do more complex sound design at the same time... It would probably beat the crap out of those vco purists  ;D

Re: Might buy a Rev2, have one question first
« Reply #24 on: August 26, 2020, 10:31:45 PM »
Ok it should arrive today and I'm currently watching your video about using the gated sequencer to make it sound a bit more not perfectly in tuned between voices.  Didn't realize how much you could do with that, very excited!

Cool - Happy New Synth Day to you!   Lemme know if you have any questions when experimenting with voice modeling.  Also, make sure to check out these free presets I uploaded here:

https://www.presetpatch.com/user/CreativeSpiral

Two template patches:
These are basically just Init patches, but with all the voice modeling wired up... you can use them to build your own sounds, or study to see how they're hooked up:
VCM_6V2O_MMChr_FFJG.syx  (6 voice emulation)
VCM_8V2O_(IIJG)_INIT_Template.syx  (8 voice emulation, intonation based tuning offsets)


And a bunch of more polished VCM patch examples:
STR_Subdiv_OBX_VCM.syx  - Rush Subdivisions
STR_DynStrings_VCM.syx - Dynamic String Ensemble
BRS_Vangel_VCM.syx - Vangelis Blade Runner
KEY_Everything2_VCM.syx - Radiohead Everything in its Right Place
STR_MegaPWM_2_VCM.syx - Big PWM String Patch
BRS_Ceremony_VCM.syx - Big Brass Patch
STR_Live_Orchestra_VCM.syx - Acoustic Ensemble String Section
KEY_ResoPluck_VCM.syx - Polyphonic Resonant Analog Pluck


Sequential Pro 3 and Rev 2 - Sound Sets and Patch Banks - Now Available on Sellfy: https://sellfy.com/sounddesign/

Re: Might buy a Rev2, have one question first
« Reply #25 on: August 27, 2020, 10:45:12 AM »
Ok, one of the first things I did was use your method with the gated sequencer to make it like a synth with some voice differences.  It sounds way better and organic.  I then made a bunch of copies of it so now most of my stuff will be based around that foundaition.  With most of my virtual voices I made, they just vary a bit randomly near 62, I didnt really to match each one up.  IE I didnt try to make osc 1 and 2 both vary in sort of the same way for each voice, I just did them all randomly in that area.  Also I used all 16 steps but on the 16th step of one I added a reset, that way the voices keep getting paired up differently for more variety(I think it works like that?).  Really awesome synth :).  I had more trouble noticing a difference in the added attack and decay in the mod matrix, but I'm sure its part of the subtle difference.  Thanks for the resources and help everyone :)

maxter

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Re: Might buy a Rev2, have one question first
« Reply #26 on: August 27, 2020, 02:07:43 PM »
Good creative thinking there, with a reset on 16, making for one line of 15 and the other 16, for a pseudo-random effect. It will take 240 consecutive notes until a repetition that way. That kind of thinking really suits the Rev2, imo, and I'm sure you'll come up with ways to cross-modulate the modulation sources with eachother for some interresting results. The mod matrix has lots of potential for this. And the LFOs and Env3 each have an extra mod destination each... Your imagination is the limit (and the few bugs still present of course, which hopefully get sorted with a new OS).

Re: Might buy a Rev2, have one question first
« Reply #27 on: August 27, 2020, 02:24:06 PM »
Ok, one of the first things I did was use your method with the gated sequencer to make it like a synth with some voice differences.  It sounds way better and organic.  I then made a bunch of copies of it so now most of my stuff will be based around that foundaition.  With most of my virtual voices I made, they just vary a bit randomly near 62, I didnt really to match each one up.  IE I didnt try to make osc 1 and 2 both vary in sort of the same way for each voice, I just did them all randomly in that area.  Also I used all 16 steps but on the 16th step of one I added a reset, that way the voices keep getting paired up differently for more variety(I think it works like that?).  Really awesome synth :).  I had more trouble noticing a difference in the added attack and decay in the mod matrix, but I'm sure its part of the subtle difference.  Thanks for the resources and help everyone :)

Yup, definitely works well with using all sixteen "virtual voices", or a mix of 15/16 if you want a different (but stable phasing) VCO character on every key strike.   

The whole virtual voice count setup with specific amounts (4v,5v,6v,8v) is meant to replicate the patterns that occur in classic synths with round-robin voice allocation.   So, if you're modeling an OBX or MemoryMoog, every 8 voices, or every 6 voices, you get returned back to that specific tuning offset for a specific voice.    It's another subtle thing, but when you play a sequence of chords, there are these minor patterns of detuning/phasing that repeat depending on how many notes are held for the chords, and what the total voice count of the synth is.  Its most noticeable if modeling a synth with one bad voice / one voice further out of tune than the others.   

In the big picture, just getting the stable tuning offsets per voice/osc will be good enough for most to capture that VCO character, but if you really want an extra level of modeling for specific classic synths, that's why I uploaded specific voice count models.... since everyone seems to want their Rev2 to sound like specific classics. 

I'm all for moving forward though, and I do use all sixteen virtual VCM voices often for my new sound designs.   It's one of the INIT templates I've got ready to go at all times.  :)

Glad you're enjoying it!  Look forward to hearing what you come up with.

Cheers, Jason
« Last Edit: August 27, 2020, 02:29:33 PM by creativespiral »

Sequential Pro 3 and Rev 2 - Sound Sets and Patch Banks - Now Available on Sellfy: https://sellfy.com/sounddesign/

Re: Might buy a Rev2, have one question first
« Reply #28 on: August 28, 2020, 06:35:14 AM »
Thanks Maxter, Spiral, and everyone else for the help.  This seems to be a very nice community.

Jason

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Re: Might buy a Rev2, have one question first
« Reply #29 on: August 28, 2020, 01:14:52 PM »
What struck me right away was how different the init patch oscillators sound on the Prophet '08 versus the Prophet 6 right out of the gate.  Rev2 and P6 oscillators sound pretty much the same on init patch, even when playing a fifth for example.  I would have expected Prophet '08 default osc sound to be identical to Rev2.

Yes, the settings of the initial basic patch of the Rev2 and '08 are different... as is the basic patch on a Tetra (which includes some panning). But they all sound the same if you get all the settings the matched up.

Re: Might buy a Rev2, have one question first
« Reply #30 on: September 15, 2020, 04:47:34 PM »
IDK what y'all are galking about, but VCO's and DCO's have huge differences.  I have been doing Analog synths for only about 7 years now, but they are easy to tell apart.  Now I did just get a Prophet rev2 and I will say as far as DCO's go theybare the best sounding DCO's I have ever heard, but Ill probably get the Prolouge also for it's 16 voice dual VCO synth nature to play uinison.  To me they are made for each other.   The rev2 has a deeper synth engine, but the prolouge will back it up and make the soind fuller and richer with it's VCO's.  VCO's are thicker than DCO's and put out more sound of pure electricity is the only way I can thinknto explain.

Re: Might buy a Rev2, have one question first
« Reply #31 on: September 15, 2020, 09:18:22 PM »
IDK what y'all are galking about, but VCO's and DCO's have huge differences.  I have been doing Analog synths for only about 7 years now, but they are easy to tell apart.  Now I did just get a Prophet rev2 and I will say as far as DCO's go theybare the best sounding DCO's I have ever heard, but Ill probably get the Prolouge also for it's 16 voice dual VCO synth nature to play uinison.  To me they are made for each other.   The rev2 has a deeper synth engine, but the prolouge will back it up and make the soind fuller and richer with it's VCO's.  VCO's are thicker than DCO's and put out more sound of pure electricity is the only way I can thinknto explain.

This is the dogma... you will notice that people tend to use only subjective terms when describing differences between VCOs and DCOs... it's widespread across the synth community, and has been for many years.  That's what actually led me on my journey to try and document the differences - I wanted to understand objectively / scientifically what the differences between DCOs and VCOs were.   I recorded hundreds of samples from dozens of synths - many classics like Yamaha CS-80, Roland Jupiter 4, Jupiter 8, Oberheim OBX, OBXa, Prophet 5, Prophet 10, Korg Polysix, Memory Moog and several other classics, as well as a variety of modern VCO and DCO synths.   There are two objective differences that can be measured: 

First, all VCOs do exhibit a small amount of frequency jitter / harmonic jitter... In a practical setting with multiple voices/oscillators playing together, it's almost impossible to distinguish between DCO and VCO.   In a situation with isolated, single, stable oscillators playing, there is a small difference though.   More info on Harmonic Freq Jitter here:  https://www.presetpatch.com/articles/VCO-Harmonic-Jitter

Second - the big difference - VCOs have inherently "bad tuning performance" over large octave ranges  (aka: Lots of Character).   If you measure even the most modern VCO implementations across a five octave range, you are almost certain to have at least 5-6 cents variance from nominal, up and down the keybed, and per oscillator, per voice.  This tuning performance is usually "intonation based".   Classic VCO synths often have 10-20 cents variance over a five octave range, sometimes even more.   They also are prone to variance with heat and humidity.   
https://www.presetpatch.com/articles/VCO-vs-DCO-Oscillators-Objective-Differences

On the other hand, DCOs are perfectly accurate up and down the keybed when it comes to nominal tuning frequency, for all voices and all oscillators.    This was what I found in my measurements that led to the Voice Component Modeling paper/article.   The "sound of VCOs" is really the sound of natural phasing of slightly detuned (but relatively stable) oscillators per voice.   On a poly synth with six voices and three oscillators, that's a total of 18 oscillators that each will have their own tuning profile across multiple octaves.   The differences between nominal target frequency and actual frequency may be small (ie: <5 cents), but when you add that up across multiple voices being played and multiple oscillators per voice, it creates this "beautiful/warm/organic/thicker *insert_your_subjective_term* "  sound.   

More info on all this here: http://www.VoiceComponentModeling.com

Sequential Pro 3 and Rev 2 - Sound Sets and Patch Banks - Now Available on Sellfy: https://sellfy.com/sounddesign/

maxter

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Re: Might buy a Rev2, have one question first
« Reply #32 on: September 16, 2020, 05:40:19 AM »
IDK what y'all are galking about, but VCO's and DCO's have huge differences.  I have been doing Analog synths for only about 7 years now, but they are easy to tell apart.  Now I did just get a Prophet rev2 and I will say as far as DCO's go theybare the best sounding DCO's I have ever heard, but Ill probably get the Prolouge also for it's 16 voice dual VCO synth nature to play uinison.  To me they are made for each other.   The rev2 has a deeper synth engine, but the prolouge will back it up and make the soind fuller and richer with it's VCO's.  VCO's are thicker than DCO's and put out more sound of pure electricity is the only way I can thinknto explain.

Please see creativespirals articles on this. The short summary and conclusion is that the Rev2 can faithfully emulate the different characteristics of VCOs by using LFOs and Gated Sequencers in Key Step mode. The cost is a couple of Mod slots, and then the Rev2 can actually act as different VCO synths (different filters aside, of course)

Re: Might buy a Rev2, have one question first
« Reply #33 on: September 16, 2020, 06:15:31 AM »
https://youtu.be/uIyK0CwmV8c

Here is a Chroma Polaris behind a Prophet Rev2. The Polaris went noticable out of tune once and I was able to get it back in tune by playing it out near the end.  There is also a tuning slider right on the front panel.  Half way through the rev2 volume cuts out and I was able to play it back in w/o to many issues.

  I almost didn't get this one bevause the youtube videos made it sound weak, but was pleasently surprised at how thick it was. 

But in essence what the above poster posted above about VCO's and DCO's are true and that is why VCO's sound so good because they will fill up a filter and resonate; make it sing! 

The VCO's from the 36 year old synth tune up fine and add a lot of sonic character and bottom end meatiness to the Prohet rev2.
« Last Edit: September 16, 2020, 07:47:17 AM by ryankm »