Pitch of Complex Tones Having Many High-Order Harmonics

Four experiments are reported which deal with pitch perception of harmonic complex tones containing many high-order, aurally unresolvable partials. Melodic-interval identilication performance ill the case of sounds with increasing harmonic order remains significantly above chalice level, even if the range of harmonics extends from the 20th to the 30th. Just-noticeable differences in pitch of the missing fundamental increase with harmonic order, but level off at about 5 Hz when the lowest harmonic is the 12th or higher. These results suggest the existence of two separate pitch mechanisms in the auditory system. A primary mechanism matches low-order, resolved harmonics to a harmonic template, as described in Goldstein 's optimum processor theory or Terhardt's virtual pitch theory. A secondary mechanism operates on dusters of high-order unresolved harmonics in a manner described by Schouten's residue theory.