SuperCollider

"SuperCollider is an environment and programming language for real time audio synthesis and algorithmic composition. It provides an interpreted object-oriented language which functions as a network client to a state of the art, realtime sound synthesis server. SuperCollider was written by James McCartney over a period of many years, and is now an open source project maintained and developed by various people."

http://supercollider.sourceforge.net/
http://en.wikipedia.org/wiki/SuperCollider

Related:

ixiQuarks - An example of the use of the GUI capabilities afforded by the SuperCollider GUI classes. ixiQuarks is a 3rd party library for SuperCollider, by the ixi team. First release: June 21st, 2007.
http://www.ixi-audio.net/content/software.html

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