Monaural/Binaural Minimum Audible Angles for a Moving Sound Source

Abstract

Papers on monaural localization relating to the action of the vestibular apparatus, influence of the auricle, and movements of the head were reviewed. To test one conclusion of the review, that a moving sound source should yield a continuous set of changing loudness/phase/timing cues available to the ear, an experiment was conducted which provides more complete quantification of monaural/binaural comparison. Minimum audible angles (maa) were computed from the responses of three men, highly experienced in listening, to white noise and tones produced by a moving sound source. The men listened (1) with both ears open, and (2) with one ear plugged, muffed, and noise-masked. The monaural maa at 0° and 60° az were as good as the binaural maa for white noise, and for the lowest tone at 0° az, but distinctly inferior elsewhere. Both azimuth and monaural/binaural mode effects reached high significance statistically. The data show much usable directionality for the monaural mode.