Dual VCA

You can never have enough VCAs, a common meme in modular synthesis declares. While this module certainly cannot fill that infinite gap, it does provide two handy voltage controlled amplifiers. They are linear, DC coupled VCAs, suitable for both audio and CV processing.

The control inputs have dedicated attenuators, and each VCA can be manually opened with the Bias control. Finally, the module has a built-in mixer, summing the output of both VCAs and one auxiliary input into the Sum Out jack. This way, for example, multiple units can be daisy-chained to form a multichannel voltage controlled mixer.

The module is built around the AS3360 dual VCA chip, a clone of the CEM3360. This chip is easy to implement, reasonably priced and has decent performance. The rest of the circuit is implemented with 0805 SMD parts.

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