[sdiy] Dealing with velocity sensitivity / scaling on envelopes

[Oakley Sound]

For polysynths with multiple voices changing the level of the VCA ADSR 
works well enough. But on monosynths you do end up with this horrible 
jump in volume when moving from a high velocity note to a low velocity 
note. Generally I avoid using such a patch on monosynth sounds unless 
the release time is very short.

However, what is more effective is control over the VCF ADSR's 
modulation level only via velocity. You do still get an abrupt change in 
CV output but it sounds better. This mimics natural sounds well too 
since louder sounds are typically brighter too.

So a velocity controlled EG is a good option since on some patches it 
will work very well but it should be able to be turned off at the very 
least.

Return to zero envelopes (RTZ), ie. ones that always start from zero on 
a note on, inevitably sound bad. Korgs & Spectrasonics among others are 
offenders here - they have RTZ envelopes whether you want them or not. 
An RTZ EG is a nice option but it shouldn't be a default setting.

Primitive samplers can have the same RTZ problem when trying to play 
monophonically too as the sample is always played from the start at note on.

It should be noted that RTZ envelopes are used in some classic string 
machines, eg. Solina, RS-505. But they really they do sound pants 
compared to proper polyphony.

Tony

www.oakleysound.com