Speech intelligibility and MTF in non-exponential decay fields

SI (speech intelligibility) tests were performed in nonexponentially-decaying reverberant fields using both Japanese monosyllables and Dutch PB words. It is shown that Si depends mainly on the initial portion of the reverberant energy decay curve (REDC). The authors also compared SI scores with the MTF (modulation transfer function), and it is demonstrated that the initial portion of REDC governs both SI scores and MTF. SI scores can be estimated from MTF by using the reverberation time from the initial portion of the REDC. Binaural effects on SI scores in the reverberant fields are also considered