Signal duration required to distinguish the tone chroma, tone height, and timbre of a sound

Current auditory models suggest that pitch is a primitive feature extracted early on and then used to assist processing of timbre information in music and speech. To test this hypothesis, the number of cycles of a sound required to identify the tone chroma (note name), tone height (octave), or timbre (instrument) of a musical note was determined. There were four instruments (brass, flute, harpsichord, and strings), four octaves centered on C1, C2, C3, and C4 and four notes, C, D, E, and F. The 64 stimuli were presented randomly at a variety of durations, and, in a given session, the listener identified the stimulus within one perceptual category: tone chroma, tone height, or timbre. The results show that performance rises with duration to an asymptotic level. Performance rises fastest to the highest asymptote in the case of instrument identification, and slowest to the lowest asymptote for tone chroma. This suggests that timbre processing can proceed before detailed information about the pitch is available. [Research supported by UK RAE 2239.]