Timbre and tone height

Abstract

A sound composed of all harmonics of 131 Hz in cosine phase produces the note C3 with a buzzy timbre. One can produce similar notes that are all C's but that sound “higher” than the original C, in at least three different ways. One can (a) attenuate the lower harmonics, (b) attenuate the odd harmonics, and (c) shift the phase of either the odd or the even harmonics. Traditionally, these perceptual changes would be regarded as timbre changes because tone chroma is fixed, but these manipulations also affect the tone height of the sound. Accordingly, experiments were performed to investigate the relationship between timbre and tone height. The stimuli were presented at six octaves with fundamentals ranging from 32–1024 Hz. The listeners judged the octave of the sounds on a scale from 1 to 6. The results show that waves with the same period can produce tone-height judgments that consistently differ by more than an octave, and that a substantial component of many presumed timbre differences (e.g., between a piano and a harpsichord) is actually a tone-height difference.