[sdiy] VCO - sine output - why bother?

[David G Dixon]

> Interesting.  If using a sine core (oscillating two-pole VCF) 
> in particular, you need two outputs from the exponential 
> converter for that anyway, even if in practice people often 
> just drive a couple of resistors with a single current source 
> and call that good enough.  Having two it then seems quite 
> natural to have a third output for some other core.

Not necessarily.  If using the 2164 quad VCA as the variable resistors, then
each of these is already an expo converter in its own right, and all are
controlled by a single linear CV, suitably attenuated to give 1V/octave.