THAT-2180 based VCA (5HP)
I've done more than my fair share of lo-fi VCAs in the past, so here's one with a bit more in the way of 'fi'.
Unlike some others, this module is built around the THAT2180 Blackmer cell IC - I find it easier to use, and less prone to self-destruction, than the V2164. This is a 100% through-hole build, with everything included including a THAT2180C IC - there are a couple of different versions of the THAT2180 (A and B) but unless you're looking for insanely low levels of THD the C variant gives the best bang for the buck, so that's what I've included.
In addition there are a pair of signal inputs (unattenuated) and a pair of control-voltage inputs with associated attenuators. Prototype versions of this module had one attenuated and one unattenuated CV channel, but since the 2180 is pretty sensitive where control voltages are concerned I decided to add an attenuator to the second CV channel too - even so, it's possible to get some _very_ cool sounding distortion out of it with the levels turned up.
These modules are built with Alpha 9mm potentiometers and Davies-style knobs. In common with my other modules, the panel is fabricated from laser-cut and engraved 3mm black perspex - the panel is 5HP (~25mm) wide.