Dual Side Chain VCA

This is a VCA that is working backwards. It works like a compressor. The control voltage is reducing the gain. It is designed with the idea of a technique that’s been used many times in electronic dance music: Gain of the synth is side chained to kick drum. When the kick drum hits the volume of the synth goes down.

Gain reduction can be controlled with an audio input (for example a kick drum) and also with control voltage. When an envelope is connected to the CV input it will make the gain go down in the shape of the envelope. The audio input will generate a control voltage internally and send it to the VCA for gain reduction. Attack and decay can be adjusted. Audio level adjustment will allow the user to adjust the depth of the gain reduction when audio input is used.

This is a dual unit and the VCA design is based on a 3360 VCA chip. Front panel is also made out of PCB and screen printed by hand.