Aeroacoustics of musical instruments

Musical sound can be generated from numerical solutions obtained from simple physical models of wind-instruments. We call such synthesizers virtual instruments. Crude caricatures capture the global oscillation behaviour of original instruments, providing the musician with a means of expression comparable to that obtained when playing real instruments. Music is, however, produced by details of the flow which correspond to much smaller temporal and spatial scales than the control of the global oscillation. This suggests that one has to split the physical model into two distinct parts: a simple numerical oscillator followed by a complex sound production module, driven by the output of the first module. We illustrate the background of this idea by a discussion of the clarinet, the human voice, and the trombone.General invited lecture presented by A. Hirschberg at the 12th Italian Congress on Theoretical and Applied Mechanics AIMETA '95, Napoli, 3–6 October 1995.