@synthlet/clip-amp

A two-gain-stage amplifier with a saturating curve between them

Part of Synthlet.

postGain × clip(preGain × input). Drive into the curve, a make-up trim after it, and a choice of curve — the smallest useful distortion stage, and the piece Web Audio's WaveShaperNode makes awkward because its curve is a sampled table rather than a function you drive.

Install

npm i @synthlet/clip-amp

Or npm i synthlet for every module at once.

Usage

import { registerClipAmpWorklet, ClipAmp, ClipType } from "@synthlet/clip-amp";

const ac = new AudioContext();
await registerClipAmpWorklet(ac);

const drive = ClipAmp(ac, {
  type: ClipType.Tanh,
  preGain: 4, // into the curve
  postGain: 0.5, // back down after it
});

osc.connect(drive).connect(ac.destination);

Parameters

| Param | Default | Range | Rate | Meaning | | ---------- | ------- | ------ | ------ | -------------------------------------------- | | type | 0 | 0 … 1 | k-rate | ClipType.Bypass (0) or ClipType.Tanh (1) | | preGain | 1 | 0 … 10 | k-rate | Drive into the curve | | postGain | 1 | 0 … 10 | k-rate | Make-up trim after it |

All three are k-rate. type selects a function, so crossing between two of them mid-block would splice rather than interpolate. The two gains are k-rate by choice rather than by necessity: a native GainNode in front of or behind this node does the same job at a-rate and costs nothing.

Every channel of the input is clipped, so a stereo signal stays stereo.

License

MIT © danigb