@audio/saturate-waveshaper

Waveshaper — normalized tanh or custom curve, oversampled

npm install @audio/saturate-waveshaper

import waveshaper from '@audio/saturate-waveshaper'

Applies a memoryless transfer function to every sample — normalized tanh(drive·x) by default, or your own curve function. Oversampled (windowed-sinc up → shape → windowed-sinc down) so harmonics pushed above Nyquist by the nonlinearity fold back as inaudible energy instead of audible aliasing, not a naive per-sample waveshaper.

waveshaper(data, { drive: 4, fs: 44100 })
waveshaper(data, { curve: x => x - x ** 3 / 3, fs: 44100 })  // custom transfer

| Param | Default | | |---|---|---| | drive | 2 | pre-gain into the tanh curve (ignored when curve is set) | | curve | x => tanh(drive·x)/tanh(drive) | custom (x: number) => number transfer function, applied at the oversampled rate | | fs | 44100 | sample rate | | oversample | 4 | oversample factor; 1 disables oversampling (naive, aliased) | | mix | 1 | 0..1 — wet/dry blend |

Mutates data in place and returns it (same array reference, not a copy). mix: 0 is an exact passthrough — verified bit-close (<1e-6) in the family test suite.

Use when: you need a specific custom transfer curve, or a clean tanh baseline without a particular harmonic-symmetry signature. Not for: a specific circuit-modeled color — use tube (even harmonics), transistor (odd harmonics), or tape (HF-rolled tanh) for those.

Part of the @audio/saturate family.

MIT © audiojs