Ripples (original)

Mutable Instruments' analog multimode filter, original panel: 2-pole band-pass, 2-pole and 4-pole low-pass, and a 4-pole low-pass through an internal VCA, built on the V2164 VCA chip and an LM13700 OTA.

Key features

• Outputs BP2, LP2, LP4 and LP4>VCA, the last one the "end of subtractive chain" output
• Frequency CV calibrated for 1 V/Oct tracking of the self-oscillation over 4 octaves, and a second frequency CV through the FM attenuverter
• Resonance CV: self-oscillation from 4 V, voltages above 5 V compressed for fine control of the overdrive
• GAIN input setting the VCA level of the LP4>VCA output
• Cutoff knob range 18 Hz to 18 kHz; all CV inputs handle audio-rate modulations
• Made from August 2013 to April 2020; the design is open source