Voltage Controlled Amplifier

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Audio In jack for injecting audio signals into the amplifier.

Manual level allows for setting the master gain cell level manually. This allows any audio signal present to "bleed" through the amplifier output. This control comes in handy for checking the audio signal or using for continuous "drones".

Master CV In Jack for inputting the main gain control voltage signal. Primarily, an Envelope Generator is patched into this jack, but other CVs can be used here for variable gain control of the VCA output. This input responds to a 0-5VDC control voltage which controls the master gain. No output will be present at 0V unless the manual level adjustment has been set above minimum.

Mod in jack allows for modulation sources to be input into the VCA.

Mod amt control allows for variable control of the amount the CV effects the VCA. As the control is rotated clockwise, the modulation goes from amplitude modulation through ring modulation then, back through amplitude modulation. This modulation affects the audio input signal, not the master gain.

Output level control allows for overall output level adjustment.

Main output jack provided for sending the VCA output to another module, an amplifier or headphones. The jack is a TRS jack and will source both sides of a set of headphones in dual mono.


This module is currently available. $195.00

Assembled/ tested board only: $85.00


Current draw:

V+= 9.82mA

V-= 7.70mA

PCB board dimensions:

3.125" (3-1/8") 79.38mm X 2.625" (2-5/8") 66.68mm

Mounting holes: 0.125" (1/8") 3.18mm (for 4-40 screw) 4 holes, one in each corner

Mounting hole spacing; Length: C-C= 2.925" 74.3mm, Width: C-C= 2.425" 61.6mm

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