Algebra Lite

Algebra based VCA

Algebra Lite is a single four quadrant voltage controlled amplifier based on the Analog Devices AD633. The VCA has 5 inputs X1,X2, Y1, Y2, Z and one output W.

Input X2 is subtracted for X1.

Input Y2 is subtracted for Y1.

The results of these subtractions are multiplied together and divided by 5. This gives you unity gain at 5 volts allowing two signals of typical Eurorack voltage to be multiplied together without loosing any amplitude.

The Z input is added to this value allowing a DC offset to be introduced.

All of this is output out the jack labeled W.

All inputs are bi-polar, and any unused input are internally tied to zero volts.

https://recklessexperimentationaudio.com/products/algebra-lite