Two synthesizers played as one. Every note you play sounds on an FM voice and on an analog-style subtractive voice at the same time, and a single XY pad moves between them.
The idea
FM and subtractive synthesis are good at different things. FM gives glassy attacks, bells and metallic overtones; a filtered analog oscillator gives warm body and a soft, round sustain. Duomutator plays both from the same notes and lets you decide how much of each you hear.
The two voices are layered, not morphed into each other: each renders its own sound and they are mixed at the output. Moving across the pad crossfades their levels at constant loudness; moving up and down changes how strongly both voices speak, from soft to bright and intense.
Controls
The front of the instrument keeps the everyday controls together:
- The XY pad. Left to right blends FM into analog; bottom to top raises the timbral intensity of both voices.
- Blend, Tone and Output knobs under the pad. Blend and Tone mirror the pad's two axes; Output sets the level.
- A preset picker with previous and next buttons.
Below, each voice has its own panel. Click a voice's cover to fold its panel away.
- FM voice: Harmonic Body, Inharmonic Strike (adds an operator at a non-integer ratio for a struck, bell-like edge), Brightness, Feedback, a low-pass cutoff, an amplitude envelope, a separate timbre envelope and a timbre LFO. An advanced editor opens all six operators and a routing matrix showing how each one modulates the others.
- Analog voice: one oscillator (Sine, Saw, Square or Triangle), a resonant low-pass filter and its own amplitude envelope.
Voice & Glide switches both voices together between Polyphonic, Monophonic and Mono Legato, with portamento up to two seconds.
Getting started
Duomutator is an instrument: play it from the on-screen keyboard or a MIDI controller. Start with Glass & Grain, then try Soft Current, Bright Edge, Bass Body + Attack, Evolving Haze or Spark & Body, and drag the pad while holding a chord.
Limits
Polyphony is eight notes. Changes to the FM envelopes apply to the next note you play, not to notes already ringing. The analog voice has a single oscillator.



