The WMDevices Triple Bipolar VCA is an input side expansion for the 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 through zero amplitude and the output will be inverted. 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.
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 dual VCA. Negative control voltages will open the - side, and positive control voltages will open the + side. This allows you to use two modulation sources and alternate between them, while still retaining control over amplitude.
- 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 (with 0V control voltage).
- 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.
- Three Bipolar VCAs
- Normaling to PDO
- Linear Response
- Bipolar Attenuator for CV
- Mix Output Sums All Three VCAs
- Bi-color Signal LEDs
- "-" Input for Mix Through Zero
- Skiffable PCB Design
- 8 HP
- +80mA/-75mA Current Consumption