WMD Triple Bipolar VCA

"Intoducing the WMD Triple Bipolar VCA, the input side expansion for our Phase Displacement Oscillator. This module provides dedicated inverting/polarizing/bipolar amplitude modulating inputs normaled to the Phase Modulation inputs on the PDO.

A bipolar VCA is like a normal VCA when operated with positive control voltage. But when using a negative control voltage, the output will swing back past zero amplitude and invert the signal coming out. This produces deeper modulation than a normal VCA.

The Triple Bipolar VCA is also designed to be used as a standalone module, it does not require the PDO to operate.

Features

Three Bipolar VCAs
Normaling to PDO
Linear Response
Bipolar Attenuator for CV
Mix Output Sums All Three VCAs
Bi-color Signal LED
"-" Input for Crossfading
Skiffable PCB Design
8 HP
+80mA/-75mA Current Consumption

Controls and I/O

+ In - This is the normal input for each VCA channel. It drives the inverting side of the Bipolar VCA. These inputs are normaled from outputs on the PDO.

- In - This is the second input for the VCA channel. Normaled through this jack is the inverted signal from the + Input. Plugging in here converts the channel from a Bipolar VCA to a crossfader, blending between the + and - inputs. When in crossfade mode, both inputs and the output are non-inverted.

CV - This input jack drives the CV knob. It can handle unipolar or bipolar signals.

Out - This is the output of each VCA channel. They are normaled to the Phase Modulation inputs on the PDO.

Bias Knob - Sets the manual gain for the VCA. Centered will have a zero output in bipolar mode, and 50%/50% of both + and - inputs in crossfade mode.

CV Knob - This knob is a bipolar attenuator for the signal applied to the CV jack. Spin clockwise from center for positive CV interactions, counterclockwise to invert the CV.

Mix Out - This output jack mixes the signals from each VCA."

via WMD