VCF-20 Filter

AirStep Oscillator AirVector Envelope AirWave Vector Oscillator Analog Shift Register Arpeggiator Amplifier Attenuverter Additive Oscillator

Bandpass Filter Bend Limiter Binary Blank Panel 6HP Black/White Boolean Logic

Chorus Clock Divider Console Mixer Crossfade CV To MIDI CC Converter CV To MIDI Compress

DC Source Delay Digital Reverb Diode Distortion Drum Highpass Lowpass Drum Oscillator Dual VU Meter DCO-60

Eight Step Sequencer Eight To One Switch Envelope Follower EG-20 EG Station Envelope Generator ESP-20 Processor

Filter Formula FM Station

Glide

Hex Phaser

Invert

LFO Lyrinx Filter Ladder Filter Limiter

Mega Saw Micro Burst MIDI CC Converter MIDI Channel Filter MIDI Clock Divider MIDI Drum Trigger MIDI Input MIDI Multiple MIDI Output MIDI Trigger 3 Mini LFO Mini Mono to Poly Mini Plug-In Host Mini Poly to Mono Mod Wheel Assistant Mono To Poly Mighty Piano Roll Multiple

Noise Generator Notch Filter

Octagon One To Eight Switch Oscillator Oscilloscope Octal Switch

Panner Percussion EG Plug-In Host Poly Amplifier Poly CV Converter Poly Filter Poly Glide Poly Multiple Poly Octave Oscillator Poly Oscillator Poly Six-Input Mixer Poly Stereo Spread Poly To Mono Poly Unison Phaser Poly EG-20 Poly EG Station Poly Envelope Generator Poly FM Station Poly Quantizer Poly Synthesizer Expander Module Poly Super Envelope Generator Poly VCF-20 Filter Poly VCO-20 Dual Oscillator Polymode

Quantizer

Random Task Ring Modulator Re-Animator

Sampler I Sampler II Six-Input Mixer Six-Input Stereo Mixer Splitter Spring Reverb String Chorus Sub Octave Super LFO Super Oscillator Sync Divider Sync Generator Sync To MIDI Clock Sixteen Step Sequencer Super Envelope Generator Synth Voice Sample and Hold Synthesizer Expander Module

TB Oscillator Three-Band EQ Threshold Trigger to Gate Converter

Vintage Oscillator Vocoder Voltage-Controlled Mixer VCF-20 Filter VCO-20 Dual Oscillator Vintage Resonator

Arpeggiator Micro Burst Random Task

Analog Shift Register Bend Limiter Diode Envelope Follower Glide Invert Mod Wheel Assistant Poly Glide Ring Modulator Poly Quantizer Quantizer Sample and Hold

Chorus Delay Digital Reverb Distortion Hex Phaser Spring Reverb String Chorus Three-Band EQ Vocoder Compress Limiter Phaser

Percussion EG EG-20 EG Station Envelope Generator Poly EG-20 Poly EG Station Poly Envelope Generator Poly Super Envelope Generator Super Envelope Generator

Bandpass Filter Drum Highpass Lowpass Filter Lyrinx Filter Poly Filter Ladder Filter Notch Filter Poly VCF-20 Filter VCF-20 Filter Vintage Resonator

DCO-60 Poly Synthesizer Expander Module Synth Voice Polymode Synthesizer Expander Module

Mini Plug-In Host Plug-In Host

Binary Boolean Logic Formula Threshold

Dual VU Meter

CV To MIDI CC Converter CV To MIDI MIDI CC Converter MIDI Channel Filter MIDI Clock Divider MIDI Drum Trigger MIDI Input MIDI Multiple MIDI Output MIDI Trigger 3

AirVector Envelope Console Mixer Crossfade Poly Six-Input Mixer Six-Input Mixer Six-Input Stereo Mixer Voltage-Controlled Mixer

AirStep Oscillator AirWave Vector Oscillator Drum Oscillator LFO Noise Generator Oscillator Poly Octave Oscillator Poly Oscillator Sampler I Sampler II Sub Octave Super LFO Super Oscillator TB Oscillator Vintage Oscillator FM Station Poly FM Station Poly VCO-20 Dual Oscillator VCO-20 Dual Oscillator Additive Oscillator

Mini Mono to Poly Mini Poly to Mono Mono To Poly Poly Stereo Spread Poly To Mono Poly Unison

ESP-20 Processor

Eight Step Sequencer Octagon Mighty Piano Roll Sixteen Step Sequencer

Mega Saw Mini LFO Sync Generator

Eight To One Switch One To Eight Switch Octal Switch

Blank Panel 6HP Black/White Clock Divider DC Source Panner Poly Amplifier Poly CV Converter Poly Multiple Splitter Sync Divider Sync To MIDI Clock Trigger to Gate Converter Amplifier Attenuverter Multiple

Oscilloscope Re-Animator

The Cherry Audio VCF-20 Filter is an analog-style, voltage-controllable, dual highpass/lowpass filter that recreates the aggressive tones of a classic 70s Japanese monosynth. Its uniquely raunchy sound totally transforms the overall tonality of Voltage Modular! The two resonant filters can be used individually, in series, or manually patched in various configurations and are both capable of screaming self-oscillation. We carefully A/B'd the VCF-20 Filter with the coveted "version 35" filter of the original instrument and we think you'll be delighted with its authenticity.

Inputs, Outputs and Controls

Highpass/Lowpass In jacks and Level control- These are the input jacks for the highpass and lowpass filters. Signals input here can be attenuated before being sent to the filter via their respective Level knobs. Be sure to try using these to “dial in” the filter. Changing the input level of a signal can drastically change the way the filter sounds especially when using high peak settings.

Series- Engaging this button internally routes the output of the highpass filter to the input of the lowpass filter. This is a quick way to use both filters in series with only one input patched. Note though that this bypasses the input stage level control of the lowpass filter. It is possible however to manually patch the filter in series and use both input stages.

HP Cutoff Freq- Sets the cutoff frequency of the 6 dB/oct highpass filter. All frequencies higher than this will be allowed to pass through the filter while frequencies lower than the cutoff will be attenuated at a rate of 6 dB per/octave.

LP Cutoff Freq- Sets the cutoff frequency of the 12 dB/oct lowpass filter. All frequencies lower than this will be allowed to pass through the filter while frequencies higher than the cutoff will be attenuated at a rate of 12 dB per/octave.

HP Freq CV and LP Freq CV inputs and attenuators- CV mod inputs and attenuators for externally controlling each filter’s cutoff frequency.

Peak (resonance)- Emphasizes sound energy at and around the cutoff frequency by adding feedback from the filter’s output back to its input. As the peak is increased, any modulations or knob twisting of the cutoff frequency becomes more pronounced and can create the classic “vowel-sound” this filter is known for. When turned up past seven or so, the filter begins to feed back enough to self-oscillate. (Note that unlike the original, a cable must be patched to the filter’s input to hear it self-oscillate. This is designed to save CPU when the filter is not in use.)

Peak CV inputs and attenuators- CV mod inputs and attenuators for externally controlling the peak (resonance) of each filter. This is a feature the original monosynth did not have. The resonance of this filter can get out of hand pretty quickly, so it’s quite nice to have a little extra control via the CV inputs.

Saturation- Adds distortion to the signal. Used subtly it can add extra harmonics to a smooth bass sound or some tasteful grit to a vocal sample. Higher settings will produce the aggressive character that the original is famous for. Be careful though... when used in conjunction with a high peak setting, this filter will literally scream!

About MS-style Oscillator Distortion: You may notice that VCF-20 doesn't necessarily distort in the expected way when using the standard green Voltage Modular Oscillator (especially with square waves). This is because the wacky, characteristic MS-style filter distortion is partially the result of the not-exactly-correct-on-an-oscilloscope waveforms output from the original MS synth oscillators. These "incorrect" waveshapes are accurately recreated in the VCO-20 Dual Oscillator module, so try it in conjunction with VCF-20.

Saturation CV inputs and attenuators- CV mod inputs and attenuators for externally controlling the saturation of each filter.

Highpass Out jack- Outputs the processed signal from the highpass filter.

Mix Out jack- Outputs the sum of both filters.

Lowpass/Series Out jack- Outputs the processed signal from the lowpass filter. When the Series button is engaged, this will output the signal sent to the highpass filter’s input which is then sent to the lowpass filter.