Hot topics in musical acoustics: Wind-instrument response in the time domain

Abstract

Physical modeling of sound production in the time domain has recently emerged as a useful tool for the study of musical wind instruments, with applications to instrument design and computer music synthesis. The air column response is described by a reflection function (or impulse response), defined at the location of sound regeneration in the mouthpiece or double reed. Thus experimental measurements of instrument response directly in the time domain are of great interest. One approach uses a single source and single microphone mounted in a long cylindrical tube coupled at one end to the air column. Singular value deconvolution is first used to generate an optimal band-limited impulse, and again used to calculate the reflection function from the incident and reflected pulses [J. Agulló etal., SMAC, Stockholm (1993)]. A second approach allows insertion of the source/microphone directly into the mouthpiece, thereby eliminating the need for the long tube. This may be advantageous for measurements on instruments and in applying the technique in hearing. A calibration step is added that involves measurements on a single cylindrical tube of known dimensions. Results on various wind instruments will be presented. [Work supported by NIH.]