What is it?
Tone.js is a Web Audio library which wraps and (hopefully) simplifies some of the Web Audio API.
The focus of Tone is on making interactive music:
* Musical timing - `"4n"`, `"8n"`, `"1:4:2"`, `"2m + 4t"`
* Musical notation - `"C4"`, `"Db4"`, `440`, `"440hz"`
* Precise scheduling with just in time callbacks
* Synths and effects
* Modular components to build your own
You create an audio processing graph by connecting nodes like oscillators or filters (think patch cables). Connections allow audio to flow from one node to the next.
The signal can be either audio signal or control signal (think modular synth). One example would be modulating the detune of one Oscillator with another oscillator to create vibrato.
Not all values are modulate-able with audio-rate signals. For example, you can modulate the frequency or detune of an Oscillator because these are Signals, but you can't modulate the type of an oscillator in the same way.
(In the docs, AudioParams/Signals are documented with a [~])
Signals (unlike normal parameters) are set with .value.
//NOPE
osc.frequency = 440;
//YEP
osc.frequency.value = 440;But they also offer a bunch of scheduling methods. For example ramping the frequency of an oscillator or scheduling the frequency value to change at a specific time.
Play (or don't) with some probability
Walking through a melody array
Randomly walking through a melody
Markov chains define states and probability of moving from one state to another. We'll use chords as our states and define a way of moving from one state to another.
Each element in the array represents the probability of that event happening on that page.
Tone.CtrlInterpolate with interpolate between arrays, objects, or arrays of arrays.
As shown above, Tone.js and Web Audio can do all this scheduling ahead of time and preschedule an entire song or composition (like CSound, RTCMix and many others), but a lot of the strength of the library comes from just-in-time scheduling within callbacks. This opens things up to interaction...
Change synths envelope with mouse move
Time in Web Audio starts at 0 when the page loads and is counted in seconds. Tone offers conversions from musical timing to seconds based on the current bpm of Tone.Transport.bpm.