Limitations on the range of intensity independence of pitch mixture of dichotic chords

Abstract

The relative salience of the pitch components of a two-tone dichotic chord is invariant with respect to the relative intensity of the two tones over a wide range of interaural intensity differences [R. Efron and E. W. Yund, J. Acoust. Soc. Am. 59, 889–898 (1976)]. In a recently developed model for this phenomenon, the range of intensity independence is limited by the bone-conducted energy from the more intense tone [E. W. Yund and R. Efron, J. Acoust. Soc. Am. 62, 607–617 (1977)]. The model thus predicts that a decrease in bone conduction must increase the range of intensity independence. This prediction has been confirmed by experiments using insertion earphones. The range of intensity independence with insertion earphones was 6–17 dB greater than the value obtained for the same subjects using TDH 39 earphones in MX41/AR cushions. [Work supported by the Veterans Administration.]