EFFECT OF PULSED MASKING ON SELECTED SPEECH MATERIALS

Monaural intelligibility functions for spondaic and monosyllabic words and identification functions for synthetic sentences were obtained for 14 experimental conditions of masking by random noise. The noise was presented continuously and interrupted or modulated (â14 dB interburst ratio) at rates of 1, 10, and 100 interruptions per second. The intensity levels of the maskers were 50 and 90 dB SPL. Results demonstrated that (1) masking effectiveness decreased for spondees and sentences as the interruption rate decreased; (2) the greatest release from masking for monosyllabic words was found during the 10 ips condition at favorable S/N ratios; however, at the more unfavorable S/N ratios, greater release from masking was observed during the 1 ips condition; (3) greater release from masking occurred for interrupted than for comparable modulated noise conditions. The possible effects of the interaction between the type of speech material and forward and backward masking during the silent interval between noise bursts is discussed. © 1969, Acoustical Society of America. All rights reserved.