When you tune an instrument’s individual overtones to align with steps of a scale, suddenly a tuning that’s too rough for normal instruments becomes justified for real music making. That’s spectral microtuning.
Mutant Squelch is uniquely designed to make this kind of experimentation easy. Two headline features:
Resynthesis
Drop your own audio files into Mutant Squelch, play back at any pitch and speed, through spectral FX such as Overtone Conform, Overtone Stretch and Overtone Offset.
Overtone Conform
Quantise overtones towards the nearest pitch in the tuning, with a strength from 0-100%. As Overtone Conform approaches 100%, dense upper partials of a timbre converge on scale steps, creating a chorusing that gets slower and slower until the timbre is beatless and justified.
Oscillator Modules
Classic: A wide selection of classic synth waveforms rendered with additive synthesis
Resynthesis: Drag-and-drop your own audio samples into Mutant Squelch and play back thru spectral effects
Modulation: Frequency, phase, ring, and amplitude modulation with 2 operators that are tuned to exact scale steps from your tuning, resulting in tuning-related sideband spectra
Geometric: Timbres formed by stacking the same interval on itself repeatedly
Arithmetic: Timbres formed by stacking the same frequency offset on itself repeatedly
Split String: An experimental string model, formed of two segments with differing length and tension
Spectral Effects
Overtone Stretch: Stretch or compress the entire spectrum
Overtone Conform: Align overtones to the currently loaded tuning
Overtone Offset: Shift overtones by a Hz value
Tuning & Pitch
Scale Files: Drop in your own scl and kbm files
MTS-ESP: Convenient tuning and scale morphs
Tuning Lock: Presets don’t unset your tuning while lock is active
Tuning Library: Example scl and kbm files included
Drift: Gentle pitch instability
Portamento: Legato pitch glides
Pitch Envelope: Kick drums and glissandi
Pitch Bend: Scale-aware bends always land on a scale step, even with unequal scales. This stays true for every voice in a held chord, letting you bend exactly from one chord to another
Filters
3-pole Diode LPF: A squelchy, acidic, resonant classic
4-pole Ladder LPF: Warm, fat, saturated
4-pole BPF: Good for sweeps, squelches and pad sounds
2-pole HPF: Resonant high-pass
Notch: Phaser-like sounds
Formant: Glide thru 5 vowel sounds
Warm: Optional low-pass to transparently roll off high frequencies
Misc
Polyphony: Polyphonic / Mono / Mono Legato
Factory Presets: Some sounds to get you started
GUI: Oldskool rack module inspired design
Colour Themes: Choose yours
Spectrum Analyser: Helps you understand wtf Overtone Conform does
Independent: Mutant Squelch is lovingly created by one guy with years of experience with microtonality, electronic music and synth design. It’s a fully-featured remake of a prototype from 2013 (my final year project at uni), and I hope it will help you and your music.
