The Black Quad VCA by Erica Synths is actually 4 independent VCAs that utilize a unique pre- and de-emphasis circuit that keeps the incoming signal pristine. The module features automatic mixing outputs and configurable CV addressing, meaning that when no CV is connected it doubles as a quad mixer.
Black Quad VCA Features
4 independent VCAs
Manual signal and CV level adjustment
Pre-emphasis – de-emphasis circuits on all 4 channels