[sdiy] MIDI Velocity on analog synths

[rsdio at sounds.wa.com]

I could be overlooking some detail, but I would say that every  
voltage except Gate should be held until the next update (and fore  
Velocity, that update comes with Note On).

I mean, envelope control voltages should progress according to their  
rate and level settings, frequency should be updated at Note On and  
held steady until a new note, and all other CV values should pretty  
much stay put until specifically updated. The Gate signal is the only  
analog thing that should change at Note Off, besides Note Off  
Velocity. Of course, envelopes will response to Gate Off by beginning  
their release, but envelope outputs are always under their own control.

Those of you with more modular experience than me (or even non- 
modular analog CV systems) are welcome to enlighten the readers if  
there's something wrong or something I've missed.

... or, to put it another way, what is a voltage supposed to change  
to when a note ends? There is no defined value other than the most  
recent value. What do analog sequencers do with the voltage between  
steps? I've always assumed that they hold the previous value until a  
new update occurs, rather than dropping back to 0 V, but I guess  
that's a potential implementation.

Brian Willoughby
Sound Consulting


On Feb 6, 2014, at 21:35, Quincas Moreira wrote:
> I have Roman's midi implant, and it has a nifty feature.  You can  
> program it with sys.ex. to hold the voltage in cv 2 (which i use  
> for velocity) until the next note-on message.  This is useful for  
> when you have a sound with long decay, so you don't get a jump in  
> the velocity value when you let go of the key.
>
> Quincas
>
> On Thu, Feb 6, 2014 at 9:35 PM, <rsdio at sounds.wa.com> wrote:
>> I was going to ask how you assigned velocity to anything with a  
>> stock Pro-One, but I suppose you used a MIDI-to-CV converter.
>>
>> Brian
>>
>> On Feb 6, 2014, at 06:14, Martin Fay wrote:
>>> As a countering point, when I had a Pro-One I used velocity to  
>>> control cutoff, so certainly _I_ found that musically useful ;)
>>>
>>> Martin
>>>
>>> On 6 Feb 2014, at 09:17, Florian Anwander <fanwander at mnet- 
>>> online.de> wrote:
>>>> Am 05.02.2014 19:11, schrieb MTG:
>>>>> I imagine when an Note-On arrives you
>>>>> apply the velocity value (voltage) to VCF Cutoff or Resonance or
>>>>> whatever,
>>>> Just aside the 0V question: I'd never direct the velocity to the  
>>>> cutoff only, but always to the amounts of the envelopes.
>>>>
>>>> Florian
>