Saxophone Input Impedance Online

Participants: Tristan Matthews and Gary Scavone

Funding: NSERC Discovery Grant

Period: 2007


The response of complex air columns, as found in woodwind instruments, can be approximated by a one-dimensional lumped model composed of cylindrical and conical segments. The tonehole transmission matrix elements proposed by Keefe (1981) can also be used in conjunction with this model to determine the input impedance of a given instrument for any fingering. However, the tonehole parameters were developed for cylindrical sections and their direct application to conical structures has not been completely investigated. An implementation of the model for the alto saxophone is presented that may be adapted to suit any woodwind instrument, given its bore and tonehole measurements. A Web-based interface is described that allows the user to obtain input impedance data by graphically selecting a fingering in a manner similar to the Virtual Flute Project [Botros, 2001]. The system also compares measured input impedance data for an alto saxophone with the theoretical results.


  • Matthews, T. and Scavone, G. “An Online System for Viewing the Input Impedance of Saxophones.” In Proceedings of the 2007 International Symposium on Musical Acoustics, Barcelona, Spain, September 2007.