[sdiy] very simple VCA circuit

[David G. Dixon]

> LOL. I'd say the same for the LM13600/700, unless you use the diode bias
> circuit. If you do, the
> VCA will clip horribly when overdriven, as opposed to the CA3080. ALL are
> noisy.
> 
> The CA3280 was the good stuff, now unavailable except at high prices from
> (often) dubious sources
> (some folk have gotten counterfits...)

I gave up on OTAs.  Now all I use is linearized 2164s (thanks, Mike Irwin!).
They're easier to design with too, and they've forced me to consider all of
my circuits from the perspective of current rather than voltage, which has
led to some new ideas.