[sdiy] CV inputs with bipolar "amount" knobs

[David G. Dixon]

> in my experience a potentiometer with center detent could cause another
> problem: you might not always have the same resistance value at the
> detented position. it may be different each time you set it back to zero.
> however, for a VCFs control voltage input it might not be crucial, and it
> may depend on the quality of the potentiometer - I tried alpha and alps
> with no luck.

Yes, I'd thought of that.  However, as you say, it's just a CV control for a
filter, so it's really not that critical.  I just listen for the centre
point anyway.