| The 24dB VCF (Voltage Controlled Filter) module is a lowpass-filter that follows the famous cascade invented by Moog.
The filter module has two audio inputs with input 1 offering variable attenuation. When not patched the filter output is fed back into this input. By this, it is easy to recreate the legendary feedback-trick that leads to additional pushing bass. Input 2 has a fixed input sensitivity that matches the Mix output of MFB's oscillator modules OSC-01 and OSC-02.
Filter cutoff can be controlled manually as well as from CV-sources. CV-1 is adjustable in intensity and intended to be used with an envelope generator. CV 2 has two functions: It accesses the internal Key-CV-voltage provided by the system-bus (when fed by a MIDI/CV-interface). This allows for easy key-tracking for the cutoff-frequency. Tracking-intensity can be adjusted by a trim-potentiometer. An additional front-panel-input allows adding a further CV-source (e.g. LFO) that uses the same potentiometer. To use this input independently, the system-bus-access can be disabled by setting a jumper on the circuit board.
Filter resonance, called emphasis in reminiscence to Moog, can also be adjusted manually and by an adjustable CV-input.
The module has a width of 40 mm (8 TE).
> tech specs
* 24 dB-Lowpass-Filter with Feedback
* adjustable Key-CV via system-bus
* two CV-inputs for filter cutoff
* CV-input for filter emphasis/resonance