# audio-effect > Audio effects – modulation, dynamics, delay, spatial, utility, distortion Latest version **1.0.1** (published 2026-04-07) · ISC license · 0 weekly downloads > **Deprecated.** This package is deprecated. ## Install ```sh npm install audio-effect pnpm add audio-effect yarn add audio-effect bun add audio-effect ``` ## Health **Score 10/100 (F)** — status: deprecated. Negative: deprecated. ## Facts | | | |---|---| | Version | 1.0.1 | | Published | 2026-04-07 | | First published | 2026-03-31 | | Weekly downloads | 0 | | License | ISC | | TypeScript types | none | | Module format | ESM | | Dependencies | 0 | | Unpacked size | 1.3 MB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 3 | | Maintainers | dy | | Keywords | audio, effect, dsp, phaser, flanger, chorus, reverb, compressor, distortion, bitcrusher | ## Links - npm: https://www.npmjs.com/package/audio-effect - Repository: https://github.com/audiojs/audio-effect - Homepage: https://github.com/audiojs/audio-effect#readme - Issues: https://github.com/audiojs/audio-effect/issues - npm.io page: https://npm.io/package/audio-effect ## Recent versions - 1.0.1 (latest) — 2026-04-07 - 1.0.0 — 2026-03-31 ## README # audio-effect Canonical audio effect implementations.
**[Modulation](#modulation)**
[Phaser](#phaser) · [Flanger](#flanger) · [Chorus](#chorus) · [Wah-wah](#wah-wah) · [Tremolo](#tremolo) · [Vibrato](#vibrato) · [Ring mod](#ring-mod) · [Pitch shifter](#pitch-shifter) · [Auto-wah](#auto-wah) **[Dynamics](#dynamics)**
[Compressor](#compressor) · [Limiter](#limiter) · [Noise gate](#noise-gate) · [Envelope follower](#envelope-follower) · [Transient shaper](#transient-shaper) · [Expander](#expander) **[Delay](#delay)**
[Delay](#delay-1) · [Multitap](#multitap) · [Ping-pong](#ping-pong) · [Reverb](#reverb) 		**[Distortion](#distortion)**
[Distortion / saturation](#distortion--saturation) · [Bitcrusher](#bitcrusher) **[Spatial](#spatial)**
[Stereo widener](#stereo-widener) · [Haas effect](#haas-effect) · [Panner](#panner) **[Utility](#utility)**
[Gain](#gain) · [Mixer](#mixer) · [Slew limiter](#slew-limiter) · [Noise shaping](#noise-shaping)
## Install ``` npm install audio-effect ``` ```js // import everything import * as fx from 'audio-effect' // import by category import { phaser, flanger, chorus, wah, autoWah, pitchShifter } from 'audio-effect/modulation' import { compressor, limiter, gate, envelope, expander } from 'audio-effect/dynamics' import { delay, multitap, pingPong, reverb } from 'audio-effect/delay' import { distortion, bitcrusher } from 'audio-effect/distortion' import { stereoWidener, haas, panner } from 'audio-effect/spatial' import { gain, mixer, slewLimiter, noiseShaping } from 'audio-effect/utility' ``` ## API All effects share one shape: ```js effect(buffer, params) // → buffer (modified in-place) ``` Takes a `Float32Array`/`Float64Array`, modifies it in-place, returns it. Pass the same params object on every call — internal state (`_phase`, `_env`, etc.) persists across blocks automatically: ```js let params = { rate: 1, depth: 0.7, fc: 1000, fs: 44100 } for (let buf of stream) phaser(buf, params) ``` Spatial effects take two channels and return `[left, right]`: ```js stereoWidener(left, right, { width: 1.5 }) // → [left, right] haas(left, right, { time: 0.02, fs: 44100 }) // → [left, right] panner(left, right, { pan: -0.5 }) // → [left, right] ``` ## Modulation LFO-driven effects that vary a parameter periodically. ### Phaser Cascade of swept allpass filters creating moving notches and peaks. **`rate`** LFO rate in Hz (default 0.5) · **`depth`** sweep depth 0–1 (default 0.7) · **`stages`** allpass stages (default 4) · **`feedback`** 0–1 (default 0.5) · **`fc`** center frequency Hz (default 1000) · **`fs`** sample rate ```js import { phaser } from 'audio-effect/modulation' let p = { rate: 0.5, depth: 0.7, stages: 4, feedback: 0.5, fc: 1000, fs: 44100 } for (let buf of stream) phaser(buf, p) ``` **Use when**: electric guitar, synth pads, vintage phase effects
**Not for**: spatial positioning (use stereoWidener or haas) ### Flanger Modulated short delay (1–10 ms) with feedback — creates comb filter sweep. **`rate`** LFO rate in Hz (default 0.3) · **`depth`** modulation depth 0–1 (default 0.7) · **`delay`** center delay in ms (default 3) · **`feedback`** 0–1 (default 0.5) · **`fs`** sample rate ```js import { flanger } from 'audio-effect/modulation' let p = { rate: 0.3, depth: 0.7, delay: 3, feedback: 0.5, fs: 44100 } for (let buf of stream) flanger(buf, p) ``` **Use when**: jet sweeps, metallic modulation, guitar/bass
**Not for**: subtle pitch modulation (use vibrato) ### Chorus Multiple detuned delay voices layered over dry signal — ensemble thickening. **`rate`** LFO rate in Hz (default 1.5) · **`depth`** modulation depth 0–1 (default 0.5) · **`delay`** center delay in ms (default 20) · **`voices`** number of chorus voices (default 3) · **`fs`** sample rate ```js import { chorus } from 'audio-effect/modulation' let p = { rate: 1.5, depth: 0.5, delay: 20, voices: 3, fs: 44100 } for (let buf of stream) chorus(buf, p) ``` **Use when**: thickening strings, vocals, synth pads
**Not for**: transparent processing (adds modulation artifacts) ### Wah-wah Swept resonant bandpass filter — auto (LFO) or fixed frequency mode. **`rate`** LFO rate in Hz (default 1.5) · **`depth`** sweep depth 0–1 (default 0.8) · **`fc`** center frequency Hz (default 1000) · **`Q`** resonance (default 5) · **`mode`** `'auto'` LFO or `'manual'` fixed (default `'auto'`) · **`fs`** sample rate ```js import { wah } from 'audio-effect/modulation' let p = { rate: 1.5, depth: 0.8, fc: 1000, Q: 5, fs: 44100 } for (let buf of stream) wah(buf, p) ``` **Use when**: classic wah sound, filter sweeps
**Not for**: signal-driven wah (use autoWah) ### Tremolo Amplitude modulation via LFO — periodic volume pulsing. **`rate`** LFO rate in Hz (default 5) · **`depth`** modulation depth 0–1 (default 0.5) · **`fs`** sample rate ```js import { tremolo } from 'audio-effect/modulation' let p = { rate: 5, depth: 0.7, fs: 44100 } for (let buf of stream) tremolo(buf, p) ``` **Use when**: vintage amp tremolo, rhythmic pulsing, guitar effects
**Not for**: pitch modulation (use vibrato) ### Vibrato Pitch modulation via modulated delay line — periodic pitch wobble. **`rate`** LFO rate in Hz (default 5) · **`depth`** delay modulation depth in seconds (default 0.003) · **`fs`** sample rate ```js import { vibrato } from 'audio-effect/modulation' let p = { rate: 5, depth: 0.003, fs: 44100 } for (let buf of stream) vibrato(buf, p) ``` **Use when**: vocal vibrato, string wobble, instrument simulation
**Not for**: amplitude variation (use tremolo) ### Ring mod Multiplies signal by a carrier oscillator — produces sum and difference frequencies. **`fc`** carrier frequency Hz (default 440) · **`mix`** wet/dry 0–1 (default 1) · **`fs`** sample rate ```js import { ringMod } from 'audio-effect/modulation' let p = { fc: 300, mix: 1, fs: 44100 } for (let buf of stream) ringMod(buf, p) ``` **Use when**: metallic/robotic tones, experimental textures, AM synthesis
**Not for**: clean frequency shifting ### Pitch shifter Granular OLA pitch shifting via varispeed read with crossfade grain boundaries. **`shift`** pitch ratio (default 1.5 · 2 = +octave · 0.5 = −octave) · **`grain`** grain size in samples (default 2048) · **`fs`** sample rate ```js import { pitchShifter } from 'audio-effect/modulation' let p = { shift: 1.5, grain: 2048, fs: 44100 } for (let buf of stream) pitchShifter(buf, p) ``` **Use when**: harmonizer, octave up/down, pitch correction
**Not for**: high-quality transposition (use phase vocoder for that) ### Auto-wah Envelope follower drives a resonant bandpass filter — signal level controls the sweep. **`base`** minimum cutoff Hz (default 300) · **`range`** sweep range Hz (default 3000) · **`Q`** resonance (default 5) · **`attack`** envelope attack seconds (default 0.002) · **`release`** envelope release seconds (default 0.1) · **`sens`** input sensitivity multiplier (default 2) · **`fs`** sample rate ```js import { autoWah } from 'audio-effect/modulation' let p = { base: 300, range: 3000, Q: 5, sens: 2, fs: 44100 } for (let buf of stream) autoWah(buf, p) ``` **Use when**: funk guitar, touch-sensitive filter sweeps, envelope filter
**Not for**: LFO-driven wah (use wah with `mode: 'auto'`) ## Dynamics Gain-control effects that respond to signal level. ### Compressor Reduces dynamic range above threshold — feedforward with envelope follower and soft knee. **`threshold`** dB (default −20) · **`ratio`** compression ratio (default 4) · **`attack`** seconds (default 0.003) · **`release`** seconds (default 0.1) · **`knee`** soft knee width dB (default 0) · **`makeupGain`** dB (default 0) · **`fs`** sample rate ```js import { compressor } from 'audio-effect/dynamics' let p = { threshold: -18, ratio: 4, attack: 0.003, release: 0.1, fs: 44100 } for (let buf of stream) compressor(buf, p) ``` **Use when**: taming peaks, bus glue, leveling vocals
**Not for**: hard limiting (use limiter) ### Limiter Hard ceiling — infinite-ratio compressor, clamps peaks to threshold. **`threshold`** linear amplitude ceiling (default 0.9) · **`release`** seconds (default 0.1) · **`fs`** sample rate ```js import { limiter } from 'audio-effect/dynamics' let p = { threshold: 0.9, release: 0.05, fs: 44100 } for (let buf of stream) limiter(buf, p) ``` **Use when**: preventing clipping, master bus ceiling, broadcast compliance
**Not for**: transparent dynamic control (use compressor) ### Noise gate Attenuates signal below threshold — cleans up noise in pauses. **`threshold`** dB (default −40) · **`range`** attenuation when closed dB (default −80) · **`attack`** seconds (default 0.001) · **`release`** seconds (default 0.05) · **`fs`** sample rate ```js import { gate } from 'audio-effect/dynamics' let p = { threshold: -30, range: -80, attack: 0.001, release: 0.05, fs: 44100 } for (let buf of stream) gate(buf, p) ``` **Use when**: removing mic bleed, drum gate, noise floor cleanup
**Not for**: compression or amplitude control ### Envelope follower Rectifies and smooths signal to extract amplitude envelope — outputs envelope as signal. **`attack`** seconds (default 0.01) · **`release`** seconds (default 0.1) · **`fs`** sample rate ```js import { envelope } from 'audio-effect/dynamics' let p = { attack: 0.005, release: 0.05, fs: 44100 } for (let buf of stream) envelope(buf, p) // buf now contains the envelope curve ``` **Use when**: sidechain source, envelope-controlled parameters, VCA control
**Not for**: gain reduction (use compressor) ### Transient shaper Separately amplifies or attenuates transient (attack) and sustain portions. **`attackGain`** transient multiplier (default 1) · **`sustainGain`** sustain multiplier (default 0) · **`fs`** sample rate ```js import { transientShaper } from 'audio-effect/dynamics' let p = { attackGain: 2, sustainGain: -0.5, fs: 44100 } for (let buf of stream) transientShaper(buf, p) ``` **Use when**: drum punch enhancement, click reduction, transient design
**Not for**: general dynamic range control ### Expander Downward expansion below threshold — attenuates quiet signals, complementing compression. **`threshold`** dB (default −40) · **`ratio`** expansion ratio > 1 (default 2) · **`range`** maximum attenuation floor dB (default −60) · **`attack`** seconds (default 0.001) · **`release`** seconds (default 0.1) · **`fs`** sample rate ```js import { expander } from 'audio-effect/dynamics' let p = { threshold: -40, ratio: 2, range: -60, attack: 0.001, release: 0.1, fs: 44100 } for (let buf of stream) expander(buf, p) ``` **Transfer function**: for each `dB < threshold`, `gainDB = max((ratio−1)×(dB−threshold), range)` | ratio | effect | |---|---| | 2 | gentle expansion, doubles apparent dynamic range | | 4 | aggressive, close to gate behavior | | ∞ | pure gate | **Use when**: subtle noise reduction, dynamic restoration, complementing compression
**Not for**: hard noise removal (use gate) ## Delay Time-based echo and reverberation effects. ### Delay Simple delay — dry signal mixed with delayed copy and optional feedback. **`time`** delay time in seconds (default 0.25) · **`feedback`** echo decay 0–1 (default 0.3) · **`mix`** wet/dry 0–1 (default 0.5) · **`fs`** sample rate ```js import { delay } from 'audio-effect/delay' let p = { time: 0.25, feedback: 0.4, mix: 0.5, fs: 44100 } for (let buf of stream) delay(buf, p) ``` **Use when**: slap-back echo, rhythmic delays, tape delay emulation
**Not for**: diffuse reverberation (use reverb) ### Multitap Multiple independent delay taps at different times with individual gains. **`taps`** array of `{ time, gain }` objects · **`fs`** sample rate ```js import { multitap } from 'audio-effect/delay' let p = { taps: [{ time: 0.1, gain: 0.6 }, { time: 0.25, gain: 0.4 }, { time: 0.4, gain: 0.2 }], fs: 44100 } for (let buf of stream) multitap(buf, p) ``` **Use when**: complex rhythmic echo patterns, vintage tape echo with multiple heads
**Not for**: simple single echo (use delay) ### Ping-pong Cross-fed stereo delay — left echo bounces to right, right to left. **`time`** delay time in seconds (default 0.25) · **`feedback`** 0–1 (default 0.3) · **`mix`** wet/dry 0–1 (default 0.5) · **`fs`** sample rate ```js import { pingPong } from 'audio-effect/delay' let p = { time: 0.15, feedback: 0.5, mix: 0.5, fs: 44100 } for (let [L, R] of stereoStream) pingPong(L, R, p) ``` **Use when**: stereo width from delays, spatial depth, rhythmic bounce effects
**Not for**: mono output ### Reverb Schroeder reverb — 4 parallel feedback comb filters with LP damping, 2 series allpass diffusers. **`decay`** reverb time 0–1 (default 0.84) · **`damping`** high-frequency rolloff 0–1 (default 0.5) · **`mix`** wet/dry 0–1 (default 0.3) · **`fs`** sample rate ```js import { reverb } from 'audio-effect/delay' let p = { decay: 0.84, damping: 0.5, mix: 0.3, fs: 44100 } for (let buf of stream) reverb(buf, p) ``` **Implementation**: 4 parallel comb delays (1277–1523 samples at 44100 Hz), LP filter on feedback path, 2 Schroeder allpass stages (277, 349 samples)
**Use when**: room ambience, plate reverb character, spatial depth
**Not for**: convolution reverb accuracy (use an IR-based approach for that) ## Distortion Non-linear waveshaping effects. ### Distortion / saturation Four waveshaping types: cubic soft clip, hard clip, tanh saturation, and wavefolding. **`drive`** distortion amount 0–1 (default 0.5, maps to 1–10× input gain) · **`type`** `'soft'` | `'hard'` | `'tanh'` | `'foldback'` (default `'soft'`) · **`mix`** wet/dry 0–1 (default 1) · **`fs`** sample rate ```js import { distortion } from 'audio-effect/distortion' // Soft saturation let p = { drive: 0.6, type: 'soft', fs: 44100 } for (let buf of stream) distortion(buf, p) // Hard clip distortion(buf, { drive: 0.8, type: 'hard' }) // Tanh (asymptotically smooth, never clips hard) distortion(buf, { drive: 0.5, type: 'tanh' }) // Wavefolding (metallic/harsh) distortion(buf, { drive: 0.7, type: 'foldback' }) ``` | type | character | clamps at ±1 | |---|---|---| | `soft` | cubic saturation, smooth knee | yes | | `hard` | brickwall clip, harsh | yes | | `tanh` | asymptotically smooth | approaches 1 | | `foldback` | metallic, complex harmonics | yes | **Use when**: guitar overdrive, tube saturation, lo-fi crunch, harmonic enrichment
**Not for**: transparent limiting (use limiter) ### Bitcrusher Sample-rate reduction (zero-order hold) + bit-depth quantization. **`bits`** target bit depth 1–24 (default 8) · **`rate`** sample rate ratio 0–1 (default 0.25, quarter rate) · **`fs`** sample rate ```js import { bitcrusher } from 'audio-effect/distortion' // 8-bit, quarter sample rate (lo-fi) let p = { bits: 8, rate: 0.25, fs: 44100 } for (let buf of stream) bitcrusher(buf, p) // Bit depth only, no rate reduction bitcrusher(buf, { bits: 4, rate: 1 }) ``` **Use when**: lo-fi aesthetics, game audio, retro console sound, stutter effects
**Not for**: smooth saturation (use distortion) ## Spatial Stereo image and positioning effects. All take `(left, right, params)` and return `[left, right]`. ### Stereo widener Mid/side processing to widen or narrow the stereo image. **`width`** 0 = mono, 1 = unchanged, 2 = full side emphasis (default 1.5) ```js import { stereoWidener } from 'audio-effect/spatial' let p = { width: 1.5 } for (let [L, R] of stereoStream) stereoWidener(L, R, p) ``` **Use when**: widening narrow mixes, mono-compatibility check (width=0), mastering
**Not for**: positioning a single source (use panner) ### Haas effect Delays one channel by 1–35 ms — creates phantom stereo from mono source. **`time`** delay in seconds (default 0.02 = 20 ms) · **`channel`** `'left'` or `'right'` (default `'right'`) · **`fs`** sample rate ```js import { haas } from 'audio-effect/spatial' let p = { time: 0.015, channel: 'right', fs: 44100 } for (let [L, R] of stereoStream) haas(L, R, p) ``` **Use when**: mono-to-stereo widening, spatial placement, drum room simulation
**Not for**: large delays (use ping-pong delay instead) ### Panner Constant-power stereo panning using cos/sin law. **`pan`** −1 = full left, 0 = center, +1 = full right (default 0) ```js import { panner } from 'audio-effect/spatial' let p = { pan: -0.3 } for (let [L, R] of stereoStream) panner(L, R, p) ``` **Use when**: placing sources in the stereo field
**Not for**: 3D spatial audio ## Utility Signal conditioning and mixing tools. ### Gain Simple level adjustment in decibels. **`dB`** gain in dB (default 0) ```js import { gain } from 'audio-effect/utility' for (let buf of stream) gain(buf, { dB: -6 }) ``` ### Mixer Sums an array of buffers with individual gain multipliers. **`channels`** array of `{ buffer, gain }` objects ```js import { mixer } from 'audio-effect/utility' let out = mixer([ { buffer: drums, gain: 0.8 }, { buffer: bass, gain: 0.7 }, { buffer: synth, gain: 0.5 }, ]) ``` **Use when**: combining signals, bus summing, stem mixing ### Slew limiter Clips the derivative — limits how fast the signal can change. **`rise`** maximum rise rate in units/second (default 1000) · **`fall`** maximum fall rate (default 1000) · **`fs`** sample rate ```js import { slewLimiter } from 'audio-effect/utility' let p = { rise: 5000, fall: 5000, fs: 44100 } for (let buf of stream) slewLimiter(buf, p) ``` **Use when**: click removal, smoothing control signals, limiting slew on CVs
**Not for**: dynamic range control ### Noise shaping Error-feedback quantization — shapes quantization noise out of the audible band. **`bits`** target bit depth (default 16) ```js import { noiseShaping } from 'audio-effect/utility' for (let buf of stream) noiseShaping(buf, { bits: 16 }) ``` **Use when**: dithering before bit-depth reduction, quantization to lower bit depths
**Not for**: audio compression (unrelated to lossy codecs) --- _Source: https://npm.io/package/audio-effect · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._