hya.io: A graph-based audio workstation

Cristiano Belloni announced the alpha release of his Web Audio DAW (digital audio workstation) this week. It’s already a very impressive tool, with the ability to combine a number of custom effects and instruments together using a graph-like interface, share and save your creations, and create new plugins using the javascript console and a custom set of libraries. MIDI support and the ability to connect a microphone are there too. I think this is going to be really powerful if people start developing plugins for it, but for now Cristiano will no doubt appreciate everyone having a play and sending feedback.

webAudioContext –> AudioContext in Chrome

The Blink team (that’s the browser engine that inside Google’s Chrome browser) have announced an Intent to Ship for unprefixed Web Audio context. That means that in an upcoming release of Chrome (TBC), AudioContext should be used in preference to webkitAudioContext. This is great news for interoperability with Firefox’s Web Audio implementation. It seems like for the time being, the prefixed, “legacy” implementation will remain, but if you have application that hasn’t already made the switch, there’s some tools out there to make sure your code will work in as many browsers as possible. Mozilla have a handy guide to help with the transition.


Jerome Etienne describes WebAudiox.js as “a DRY library” - it’s a collection of helper functions to make some common things easy when working with Web Audio applications. There’s some helpers for drawing waveforms to a canvas from the AnalyserNode, some that help with the repetition of loading samples into buffers and playing them, and others for positioning sound in 3d spaces. They look really useful for game programming, and if your coding style matches Jerome’s they’ll probably fit neatly into your workflow.

A little tip about AudioContext.currentTime

I’m in the process of writing an article about building a simple sequencer with Web Audio. I lost a couple of hours this week when I failed to realise that, in Chrome at least, currentTime on AudioContext doesn’t advance until a node has been created. That is

var ctx = new AudioContext

will always return zero, until you do something like


It’s unusual to create a context and then do nothing with it, but if you are just developing or debugging some timing code, it’s something to watch out for. It’s expected behaviour in Chrome for optimisation reasons, but probably something that should be clarified in the specification.

Read O’Reilly’s Web Audio API book for free

Boris Smus’s book for O’Reilly “Web Audio API” is now available to read online for free! It’s a fantastic overview of the API with some great demos to study as well. In HTML format it means that these demos work right alongside the text. As with all books about emerging web technologies, it has become a little out-of-date already in places but don’t worry, you have Web Audio Weekly to keep you up to date ;).

“Biscuit tins made of sound”

I left you last time with 90 minutes of synth geekery. This week the time-deprived among you might prefer this 10 minute Vinyl Factory documentary on the story of the BBC Radiophonic Workshop. Featuring interviews with some of the surviving members of the legendary BBC outfit.