MODULE 2100 - VOLTAGE CONTROLLED FILTER

The 2100 Voltage Controlled Lowpass Filter is an exponentially controlled lowpass filter with variable Q for electronic music applications. The top two signal inputs pass through their respective attenuators and are summed with the full level input to form the total signal input. This signal is then lowpass filtered with a cutoff frequency determined by the sum of the initial cutoff frequency controls and the control inputs. The cutoff slope is 24 dB/octave, and the signal path is DC coupled. The control inputs are algebraically summed to give a total control input voltage, which will vary the cutoff frequency one octave per volt around the initial cutoff frequency. The keyboard switch allows instant patching of either of two keyboards at precisely one volt per octave. The 1V/octave control input jack is also accurately calibrated.