
"The module C 906A contains a voltage controlled low pass filter unit with a slope of -30dB/oct and two voltage controlled amplifiers in a chain.
The filter unit has a controller for the resonance (regeneration) which can be tuned until self oscillation.
With the switch "Return On" it is possible to lead parts of the output signal back to the filter which allows very deep bass - even until distortion.
With the switch named "VCF F/A" it is possible to link either only the VCF signal or the filer and amplifier signal to the output jack.
The filter has two control inputs. If the filter is tuned to self-oscillation, the input "V/Oct." enables to play the filter as a tuned sinus oscillator.
The left control input is internally connected with the left control input of the VCA. When plugging in a patch cord, this connection is cancelled and the VCA awaits an external control signal.
The "+2nd" input is always open. When plugging in a patch cord, then it can only be opened by an external control signal.
The "Main Out" pot controls the volume of the output sum."
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johnlrice