Beat Detection Using JavaScript and the Web Audio API

A great article from Joe Sullivan on performing beat detection using the Web Audio API. I like the way Joe takes us through the technique in an experimental way rather than just introducing the algorithm and its implementation.

Web Audio Hackday

If you can get yourself to Berlin on the 12th September, SoundCloud are hosting what looks to be a fantastic day of workshops and Web Audio hacking. I’m really excited to see what comes out of the day, and will keep an eye on things to feature here in the newsletter. The hackday is happening just before, so if you’re in Berlin for that make sure to sign up.


Lonce Wyse, professor at the National University of Singapore, has developed a new library to make sharing Web Audio code easier. It provides a consistent interface for a given group of Web Audio nodes. Working at a slightly higher level than native Web Audio allows more complicated building blocks to be connected together. The projects website gives a lot of different examples including a vowel synthesiser, a Karplus-Strong string synthesiser.

Audio Sort

A visualisation of various sorting algorithms accompanied by synthesised “audibilizations”. The project uses timbre.js which is a pure-javascript audio library with a flash fallback for older browsers.

Qwerty Hancock

Need an instant musical keyboard for your web audio project? Stuart Memo’s spectacularly-named keyboard library, Qwerty Hancock has reached v0.4.1, with some visual tweaks and bug fixes but the same simple API and great documentation.

Extracting audio from visual information

“Researchers at MIT, Microsoft, and Adobe have developed an algorithm that can reconstruct an audio signal by analyzing minute vibrations of objects depicted in video. In one set of experiments, they were able to recover intelligible speech from the vibrations of a potato-chip bag photographed from 15 feet away through soundproof glass.”