[RequireJS](http://requirejs.org/) is a JavaScript module loader which Tone.js uses internally for dependency management. It is a powerful tool for development and deploying. Using r.js (RequireJS's optimizer) can bring package size down significantly since it will only include the modules used in your code.
To use Tone with RequireJS, add a path to the base directory where the library is stored and then refer all Tone module dependencies starting with "Tone/".
Tone.js can also be used like any other script or library by dropping the [Tone.js Build](https://raw.githubusercontent.com/TONEnoTONE/Tone.js/master/build/Tone.js) into the <head> of your page. A global called ```Tone``` will be added to the ```window```.
To use any of the presets on instruments or effects, be sure to grab the [Tone.Presets build](https://raw.githubusercontent.com/TONEnoTONE/Tone.js/master/build/Tone.Preset.js) which is not included in the default build.
Tone.js creates an AudioContext when it loads and shims it for maximum browser compatibility. The AudioContext can be found at ```Tone.context``` or from within any Object extending Tone as ```this.context```.
Tone also let's you set your own AudioContext using ```Tone.setContext```
A unique feature of the library is the oscillator-based Transport which allows for application-wide synchronization of sources and signals. The Transport allows you to register callbacks at precise moments along the timeline which are invoked right before the event with the exact time of the event. Additionally, because the Transport is implemented with an oscillator, it is capable of elaborate tempo curves and automation.
There are three methods for timing events with Tone.Transport:
```Tone.Transport.setTimeline``` will schedule an event relative to the start of the timeline. These events will start, stop and loop with the Transport.
### Tone.Transport.setInterval
like the native ```setInterval```, ```Tone.Transport.setInterval``` will schedule a repeating event at the interval specified. These events will only be invoked when the Transport is playing.
Like the underlying Web Audio API, Tone.js is built with audio-rate signal control over nearly everything. This is a powerful feature which allows for sample-accurate synchronization of multiple parameters with a single signal. Signals are built entirely without any ScriptProcessorNodes, so they do not introduce much latency and processing overhead. Instead, all signal math and logic let GainNodes and WaveShaperNodes do all of the work so that all processing is done in the underlying Assembly/C/C++ provided by the API. Signals are used extensively internally and are also useful for general DSP and control signal logic and transformations.
Each of these synthesizers can be fed to the second argument of [Tone.PolySynth](http://tonenotone.github.io/Tone.js/doc/Tone.PolySynth.html) to turn the monophonic voice into a polyphonic synthesizer.
### Presets
Each of the instruments also has a number of presets which can be found in the Tone/instrument/presets folder. These named synthesizer configurations are a starting point for exploring the features of each synthesizer.
# Effects
Tone.js also has a few stereo and mono effects which also have their own presets.