Hi peeps.
  I've been writing an app that requires volume envelopes.  I've
  implemented the envelope part myself, but I was wondering if there
  was a library about to do it.
  I ask because I realised that probably everyone on this list has
  written something that uses envelopes, and probably written it
  better and with more features than I have.
  More generally, is there a library/toolkit of audio bits and bobs
  about?
James