2hp - VCA

Linear voltage-controlled amplifier (2HP)

Based on:
Vintage VCA by Tom Wiltshire.

interactive version (top PCB)
interactive version (bottom PCB)

You can never have too many VCAs!

This simple but effective design produces unity gain for 5V CV input, scaling linearly. The potentiometer is wired as an attenuator for the incoming CV, which is also normalled to +6V so that it can be used as a level control with no CV input.

Build notes

It honestly pains me to admit through how many iterations of a 2HP VCA I've gone. Previous designs were based on circuits from Ray Wilson and Yves Usson, but in the end I found this version to work best.