Acoustic impedance spectra of classical and modern flutes

Instruments in the flute family, unlike most wind instruments, are played w ith the input of the instrument open to the atmosphere. Consequently, they operate at minima in the spectrum of acoustic input impedance. Detailed exa mination of these minima requires measurements with large dynamic range, wh ich is why the flute has not been hitherto investigated in detail. We repor t the application of a technique with high precision and large dynamic rang e to measurements of the impedance spectra of flutes. We compare the acoust ical impedance spectra of two examples of the modern orchestral Bute and an example of the classical flute. For each instrument, we measured several d ozen of the most commonly used different acoustic configurations or fingeri ngs. The results are used to explain features of the spectra of the sound p roduced, to explain performance features and diffculties of the instruments , and to explain the differences between the performances of the classical and modern instruments. Some hundreds of spectra and sound files are given in JSV+ to allow further examination. (C) 2001 Academic Press.