Surge XT's Twist oscillator ports the Mutable Instruments Plaits macro oscillator with 16 selectable synthesis models

The Twist oscillator embeds Émilie Gillet’s Plaits Eurorack macro oscillator, exposing all 16 of its synthesis models (virtual-analog, waveshaping, FM, granular, wavetable, chord, speech/vowel, noise, particle, string and modal physical models, etc.) in a single oscillator slot. Selecting a model dynamically renames the two Twist-specific controls (Harmonics, Timbre, plus Morph) to match that model’s function, so one oscillator can be a subtractive VA, a two-operator FM voice, or a modal resonator by changing a menu. Unlike the hardware, Plaits’ internal Low-Pass Gate (LPG) is disabled by default and must be activated (right-click Activate on the LPG level/decay sliders) to be triggered per voice. A Mix parameter blends the model’s main and auxiliary outputs, and can optionally pan them across the stereo field. Twist is more CPU-demanding than most Surge oscillators.

Examples

Set Twist to the FM model for a bright two-operator bell; switch the same slot to the Modal model for a struck-resonator tone — Harmonics/Timbre/Morph re-map to each model’s controls automatically.

Assessment

What does changing the Twist model do to the meaning of its Harmonics and Timbre controls? Why must you activate the LPG explicitly, and what does it do when enabled?