Oakley Modular Euro Classic VCA (Thru-Hole 8HP)

This is a high quality single channel voltage controlled amplifier designed around an all discrete transistor core. It is based on the 4019 sub-module which is found in the classic 2600 semi-modular synthesiser.

Two signal inputs are provided, one DC coupled and the other AC coupled. The former allows audio and low frequency signals to be processed. While the latter provides a DC block to process only alternating frequencies. Both inputs can be used simultaneously and each one features an input level control.

The unit features both linear and exponential control voltage (CV) inputs. Both can be used together or individually.

A gain control is also available to provide a fixed bias to set the initial gain of the VCA. This way a negatively going CV can reduce the overall gain of the VCA. The gain pot can also be used a volume control.

Current draw with a +/-12V supply is around +/-20mA with no output signal. A standard eurorack power header is provided on the board.

The PCB is double sided with through plated holes. The topside of the board is clearly legended for easy construction. The board size is 69mm (deep) x 102mm (height).

The control pots are Alpha/ALPS 16mm types and for extra rigidity can be optionally mounted with matching brackets. Because the board is designed to mounted to the panel with the pots no other mounting holes are provided on the PCB.