[sdiy] Change response from Lin to Log to Lin to Exp?

[Neil Johnson]

Hi Justin,

>>A diff-amp across the VCA?  That would make the blue curve look like
> the green curve.
>
> I assume you mean a single input Differentiator - not a dual input Differential?

No, a 2-input difference (differential) amplifier

http://en.wikipedia.org/wiki/Differential_amplifier#Other_differential_amplifiers

What you want is to subtract the output of the VCA from the input to
the VCA, so as the VCA passes more signal, the difference between the
input and output decreases.

Of course if the VCA introduces any phase shifts as the CV is changed
that will mess things up a bit, especially the offness.  I guess how
important that is depends on the intended application.

Neil
-- 
http://www.njohnson.co.uk