Cathal Doherty

The development of a prototype Pulsar synthesizer with the W3C Web Audio API

For this thesis project a prototype for an experimental kind of granular synthesiser was constructed using the W3C Web Audio API. This type of synthesiser is known as a “Pulsar Synthesizer”. This plugin was first produced in SuperCollider in 2001 by one of its creator’s, Curtis Roads. Since then there have been a few implementations with other software programs, but there has never been one constructed as a web interface using the Web Audio APIs. By using JavaScript and HTML programming in tandem with the W3C Web Audio API many different audio processors and synthesizers can be constructed, just like the kinds of uses a programer would get out of SuperCollider and Csound.

Experimental electronic music tools are known for their rarity and obscureness. Many of which are programmed using various different languages. One of which that was first programmed in SuperCollider in 2001 by Curtis Roads and Alberto de Campo was, Pulsar Synthesis. Since then there have been a number of implementations with other software programs. However, there has never been a implementation of one using the W3C Web Audio API. For this thesis a prototype plugin was devised using the programming languages of this API, by working with HTML and JavaScript in tandem to construct a Pulsar Synthesizer. Many of the other commercially and freely available pulsar synthesizers were investigated as well as other Web Audio applications in order to work out what is the best possible solution of constructing such a synthesizer. In Pulsar synthesis one of its main features is the ability to create arbitrarily shaped envelopes to control and sculpt the sound over time. One of the ways in which this was achieved was through the use of transfer functions and the WaveShaperNode to create arbitrary shapes. Many different types of pulsar trains of varying timbres and rhythmic structures were produced by using a multitude of wave shaped signals as low frequency oscillators modulating or enveloping another oscillator.