Voltage Controlled Amplifier Board

The VCA accepts an audio input and utilizes 0-5V control voltages to control the output gain.

The main output level allows for attenuating the final output level.

The level-adjust control works in parallel with the CV input to apply a manual 0-5V to the final output gain. This opens up the output to allow for drones or a variety of audio bleed levels.

The modulation amount control increases the level of amplitude modulation applied to the primary gain cells. As more modulation signal is applied, the modulation goes from amplitude modulation and morphs into ring modulation. Further rotation of the modulation control passes ring modulation and injects increasing levels if inverted phase carrier to the signal.

The output jack is a TRS "stereo" jack that applies two buffered, identical mono outputs to the tip and ring terminals. This configuration lets the output feed both sides of a set of headphones if they're plugged into the jack for monitoring purposes.

The audio input and output are capacitively coupled to remove any DC components of the audio signal. This was necessary to implement the AM-Ring morphing feature. Therefore, any slow, DC CV applied will only create an initial change and zero out quickly.

For VCA applications for CV's, see the VC Mixer board.