mutable instruments ripples v1 price : $199.00   $149.00

ripples delivers a classic, big-sounding four-pole filter in a small 8-hp package, continuing mutable instruments' lineage of warm and tasty filters started by the shruthi smr4 mkii and 4-pole mission.

3 filter modes are available: 2-pole band-pass, 2-pole low-pass, and 4-pole low-pass.

self-oscillation is available for all modes and produces a clean sine-wave on the lp4 output. unlike many classic 4-pole designs, this filter does not suffer from "loudness drop" when resonance is increased. the resonance loudness compensation circuit brings a slight tone coloration reminiscent of the roland sh/jupiter filters, with a very round and "liquid" resonance.

the 4-pole low-pass output is additionally sent to a vca. this makes ripples a good "final stage" module for an inexpensive/space-constrained subtractive synthesis synth voice.

specifications:

inputs:
signal in
frequency cv 1 (1v/oct)
resonance cv. self oscillation starts at 4v. control voltages above 5v are non-linearly compressed, for fine control of resonance overdrive
frequency cv 2 (with bipolar attenuator, from -1v/oct to 1v/oct)
vca level. control voltages above 5v are non-linearly compressed.

controls:
cutoff frequency, 18hz to 18khz
resonance (self oscillation at 80%)
attenuverter on frequency cv

outputs:
2-pole bp
2-pole lp
4-pole lp
4-pole lp attenuated by vca

technical characteristics:
frequency cv inputs impedance: 100k.
audio input impedance: 75k.
resonance and vca cv input impedance: 30k.
open-source hardware.
8-hp.
current consumption: +12v: 35ma ; -12v: 35ma.

download the quickstart guide here.