syncopator for audio scripting

Usage no npm install needed!

<script type="module">
  import jsynthSync from 'https://cdn.skypack.dev/jsynth-sync';



A syncopation module for jsynth, baudio, and webaudio;

how to use it

see also the example

The constructor requires beatsPerMinute and SampleRate values.

var sync = require('jsynth-sync');

var timer = sync(72, 8000) // 72 bpm, samplRate 8000 (8k samples per second)
var t = timer.on(1, function(time, beatCount, clearFN, swingFN){
    // do something every beat
var i = timer.on(1/2, function(t, b, clrFN){
    // do something every half beat

function synth(t){

    timer.tick.apply(timer, arguments)



sync.on(beatValue, fn)

timer will call fn every beatValue. the return of sync.on() is a function which clears fn from being called any more. Your function will be called with the actual clock time of the call, a count for the beatValue, and a function you can call to clear the current call for good.

var quarter = sync.on(1/4, function(time, beatCount, clear, swing){
    // do something every quarter-beat
    // beatCount is the # of times this beatValue has been called.
    if(beatCount % 4 == 0) // only do something every 4th quarter beat
    if(forSomeReason) clear() // clear the timer 
  // the siwng function allows you to have the next beat (or all beats)
  // changed to a new interval
  if(true) swing(interval)
  else if(true) swing(0) // you must set it back manually

    quarter() // clears it
}, 4000)


Timer tick does not require any arguments, but will pass them on to your function. Simply call it for every sample.


clear all the timered functions