Binaural release from masking for speech and gain in intelligibility.

Relative importance of different frequency regions in binaural release from masking (for detection) and binaural gain in intelligibility was investigated. Experiments showed that the release from masking (SπN0 case) for single words in high‐level, broad‐band Gaussian noise is roughly 13 dB and is determined primarily by interaural phase opposition in the low‐frequency (<500 Hz) region. The binaural gain in intelligibility at the 50% level was on the order of 6 dB and only partly dependent on interaural phase opposition in the low‐frequency region. Interaural amplitude differences were not considered in the investigation. Subjecting the speech to a large interaural time dealy with the noise binaurally in phase resulted in a relatively constant masking level difference approaching 13 dB over the measured range from 0.5 to 10 msec. The corresponding binaural gain in intelligibility at the 50% level was on the order of 3 dB.