Just some notes:
- Use Alsamixer and arecord to get the data: http://jordilin.wordpress.com/2006/07/28/howto-recording-audio-from-the-comma...
- See also http://www.acronymchile.com/sigproc.html for notes on mono recording and analysis.
- Pipewave command line tools: http://www.cf.ac.uk/psych/home2/CullingJ/pipewave.html
