optocouplers (was:RE: Re[4] ...)

[Christopher_List at Sonymusic.Com]

  > With OTAs you always have to apply a feedback loop to get
  > "RC-type" exponential slopes.
  > With Photocouplers (LDR ...) you have a true variable resistor,
  > so exponential slopes.
  > But the Optocouplers ... wouldn't they be quite *linear*
  > (i.e. nearly constant current charge/discharge) ?
  >
  > I hope this will not ruin the whole thing ... If you have to add feedback
  > as well, the major advantages would be gone (ease of use and
  > potential-free action).

  When you say "add feedback" - do you mean running the output of the adsr
  to the VC time inputs?
  I personally find this to be a feature, and, therefore, prefer envelope
  generators with linear slopes  - as it allows for;
  1. Linear slopes (no feedback)
  2. Expo slopes (normal feedback)
  3. Reverse-expo slopes (invert the signal, then feed it back)

  - CList