MMF-1

Multimode Filter

The MMF-1 is the most flexible single filter. Additionally, the solution with variable SPACING (bandwidth) and two variable resonance peaks make it possible to create various vocal like sounds.
The Multi Mode Filter offers seven types of modes:
* Low pass
* High pass
* Band pass
* Dual band pass-------with dual resonance (Q-PEAK) and controlled bandwidth by SPACING
* Dual band pass-------with single upper resonance (Q-PEAK) and controlled bandwidth by SPACING
* Dual band pass-------with single lower resonance (Q-PEAK) and controlled bandwidth by SPACING
* Notch------------------with single or dual resonance (Q-PEAK) and controlled bandwidth by SPACING
The POLE defines how steep the filter cuts off the attenuated frequencies. It means, that the 2 pole filter cuts signal with 12dB/octave, the 4 pole filter cuts with 24 dB/octave. The higher the slope, the more effective the filter cuts. The CUTOFF frequency or corner frequency defines at which frequency the filter starts to attenuate frequencies of the incoming signal. The cutoff frequency of the filter can be adjusted by CUTOFF knob from 16kHz to 16Hz and tracked by the external signals CUTOFF CV1 and CV2.
The Q-PEAK (also known as "resonance" or "emphasis") boost audio signals in the near range of the cutoff frequency and makes the tone sound more "cutting". From a certain level on, the filter starts to self-oscillate and works as a sine wave-oscillator and in dual band pass mode (in dual Q-PEAK mode) produces two-tone sinus wave (the two-tones frequencies are controlled by CUTOFF and SPACING).
The q-peak can be controlled by knob Q-PEAK and/or by signal from levelled input Q-PEAK CV, levelled by Q-PEAK CV knob.
The SPACING control defines bandwidth for all three dual band pass modes and/or spread of two resonant peaks. The amount of spacing can be controlled by knob SPACING and/or by signal from input SPACING CV.
The audio knobs AUDIO1 and 2 controls the audio signals level coming from inputs AUDIO1 and AUDIO2.
The audio output is provided by output socket labelled AUDIO and is revealed by white surround.