Effect of Reflections on Speech Intelligibility with Different Reverberation Times

This work investigated the effect of reflections on speech intelligibility (SI) using binaural auralization technology. Firstly, speech reception threshold, which is the subjective indicator of SI, was measured by one-up-one-down adaptive paradigm; then, two objective indicators of SI (inter-aural cross-correlation coefficient and better-ear speech transmission index) were calculated. Consistent results from both subjective and objective indicators show that (1) both early and late reflections are harmful to SI; (2) for short reverberation time, the negative effect of the late reflection on SI is insignificant, while this negative effect gradually becomes obvious with the increase of reverberation time; (3) as to the early reflection, its negative effect on SI is always significant, and increases with the increase of reverberation time.