hYPerSonic allows one to build and manipulate signal processing pipelines from python scripts. It is designed for real-time control. It includes objects for oscillators, filters, file-io, soundcard and memory operations. It is low-level: every byte counts. Source code, examples, docs, here: http://arrowtheory.com/software/hypersonic/index.html Runs on Linux and OSX, with python2.2 or 2.3. I'd like to know what you think of it. Simon Burton.