Find a mechanical piano. Gently depress and hold the keys C, E, G, C' in any octave near the middle so they don't sound. That takes the felt off the strings.

Find a mechanical piano. Gently depress and hold the keys C, E, G, C' in any octave near the middle so they don't sound. That takes the felt off the strings. Now with the strongest finger on your other hand, wallop the D next to the initial C as hard as you can while still holding the C major chord keys. Release the D key and listen... The harmonics damp out at different times and leave certain overtones ringing. A high pure tone is last on a well tuned piano. My joanna gives an interestingly rich range of organ-like tones first though. Now imagine synthesising all of that dynamically for arbitrary chords, note length, pedalling &c and you have your problem space!! Domain relevant accoustic experience: track down a recording of Charlemagne Palestine's Strumming Music and listen to it on good quality headphones. His original recording (the one with the subway train going under the building as the last notes ring) was performed on his preferred Bosendorfer Imperial piano which has an extra half octave in the Bass end of the keyboard. No music written for those notes, but they don't half change the sound. Background physics: http://homepages.abdn.ac.uk/mth192/pages/html/maths-music.html http://homepages.abdn.ac.uk/mth192/pages/html/maths-music.ht... Best of luck! Tell us what you come up with. puredata might be a platform for rapid prototyping.