Pitch of dichotically presented amplitude modulated sinusoids

Abstract

Periodicity pitch resulting from dichotic presentation of harmonically related tonal complexes generated by amplitude modulation of pure tones was investigated. In the first experiment, AM signals were presented dichotically in such a way that if the individual components from each ear were combined and rank ordered, a single pitch was heard. Otherwise, separate pitches were heard at each ear. Pitch fusion was investigated as a function of frequency spacing between components and frequency region. In the second experiment, loudness balances were attempted at each ear for the periodicity pitch percept as a function of the intensity of tonal complexes. (identical to those used in the first experiment) at the other ear. The purpose of this experiment was to determine if pitch strength of tonal complexes could be increased at one ear by the simultaneous presentation os a complementary complex at the other ear. The results of the experiments are discussed in terms of the time fine-structure theories, the pattern-transformation theory, and the optimum processor theory.