Math / Other - Signal Shaper
Wavefolder. It folds values back when they exceed the fold amount, adding strong harmonics; moderate drive sounds more controlled.
Use moderate values first, then increase modulation depth while listening for clipping, aliasing, or excessive filter resonance.
fold(2.2*sin(X), 0.8)
fold() is a mathematical signal processor, not an oscillator. Pass an oscillator, filtered signal, envelope, or other expression into its first argument.