Interfamily timbral differences: A comparison of trombone and flute tone spectra

Abstract

Time‐averaged spectra for tones of the trombone and flute performed at the same pitch can be quite similar [D. A. Luce, J. Audio Eng. Soc. 23, 565–568 (1975)], and yet the tones sound quite different. Besides factors of attack rate and noise content, strong differences between the two types of sounds can be observed due to the manner in which partial amplitudes change as a function of overall (rms) amplitude. As rms amplitude increases, trombone partial amplitudes increase smoothly, resulting in an increasing spectral centroid, and as rms amplitude decreases, they follow approximately the same curves. On the other hand, amplitudes of flute partials tend to “turn on” at certain thresholds, depending on performed attack and overall amplitude, and follow different curves during ascending and descending portions of the tone. Using analysis and synthesis techniques, it is possible to create hybrid tones that blend some of the characteristics of the flute with those of the trombone, in order to evaluate the perceptual importance of distinctive parameters.