Perception and Analysis of the Difference Tone Phenomenon as an Environmental Event

Abstract

A two-phase investigation was performed to gather descriptive data on difference tone perception and to determine whether the difference tone exists as a physical entity in the environment. Descriptive data were obtained from 40 music major and nonmusic major subjects who were presented with two simultaneously sounding pure tones of varying intervals. Results indicated that the difference tone is perceived at approximately 70 db and an average 30 db difference between the sounding primaries can be withstood prior to perceptual loss of the difference tone. Environmental data were obtained by spectral analysis of sound produced by two individually amplified pure tones. The data indicated that the difference tone exists within the environment at a level of 40 db below the two 70 db sounding primaries. The results suggest that the intensity criteria necessary for difference tone perception frequently occur in music performance and may have distinct effects on perceived tone quality.