The Equation Composer has six parameters: PRG selects the active program, SR is the sampling rate which detemines playback frequency and pitch. MOD selects sounds within a program. Parameters 1-3 have an influence on the sound. All aforementioned parameters have CV inputs; when a cable is inserted the according potentiometer becomes a CV attenuator. Also, there's a gate input for triggering or resetting playback.
The module includes nine programs; it's possible to load other programs via USB. Following programs can be chosen from:
- 3 banks of different Equation Playback modes: These generate audio based on equations, ranging from self-modifying random melodies over drones to totally atonal digital noise. MOD selects between one of 40 equations, potentiometers 1-3 affect equation parameters p1-3
- Drum Selector is a prefect soure for warp-ish digital, rough drum sounds. MOD selelects the sound, Gate plays it, P1 activates freeze effect and P2 controls the wave folder.
- Wavetable & WaveFolder: Simple Wavetable VCO followed by a wave folder and a resonant low pass filter.
- Patterns plays melodies. This program combines two independent pattern generators for CVs and gates with a wave table synth. The CV pattern can be selected independent of the gate pattern and the controllable gate density allows for beautiful rhythmical variations. Sound pretty rough, cold and digital, like a 8Bit synth fro mthe early 80s.
- Chords is a wavetable based chord generator. Scale, chord and base note can be set and there are two wavetable parameters.
- 3 Oscillator contains two main oscillators detunable ± a quartertone, a sub-oscillator and a resonant low pass filter. MOD selects the waveforms from 16 oscillator configurations. Filter cutoff and resonance are controllable, too.
- Drum Player combines a drum machine and a sample player with variable sample rate. Select between different drum kits and individual patterns for bassdrum, snare and hihats.
Some more programs can be downloaded from the manufacturer's page and loaded into the module via USB, e.g. a variation of the Equation Player (but with controllable playback position and loop length), a rhythmical bouncing-ball synthesizer, a formant synthesizer and a wavetable synth with delay.
As the Equation Composer is based on the powerful arduino Due chip, you can write your own programs or modify existing ones. The software is open source. On the rear of the module there's a 14-pin expansion port.
CV inputs: program, sample rate and modification. sound parameter CV inputs 1-3
gate input, signal output
USB socket (type B)
3U Eurorack module, 12HP wide, <40mm deep, current draw: 17mA @ +12V, 17mA @ -12V and 165mA @ +5V