Listening effort and speech intelligibility in listening situations affected by noise and reverberation.
This study compared the combined effect of noise and reverberation on listening effort and speech intelligibility to predictions of the speech transmission index (STI). Listening effort was measured in normal-hearing subjects using a scaling procedure. Speech intelligibility scores were measured in the same subjects and conditions: (a) Speech-shaped noise as the only interfering factor, (b) + (c) fixed signal-to-noise ratios (SNRs) of 0 or 7 dB and reverberation as detrimental factors, and (d) reverberation as the only detrimental factor. In each condition, SNR and reverberation were combined to produce STI values of 0.17, 0.30, 0.43, 0.57, and 0.70, respectively. Listening effort always decreased with increasing STI, thus enabling a rough prediction, but a significant bias was observed indicating that listening effort was lower in reverberation only than in noise only at the same STI for one type of impulse responses. Accordingly, speech intelligibility increased with increasing STI and was significantly better in reverberation only than in noise only at the same STI. Further analyses showed that the broadband reverberation time is not always a good estimate of speech degradation in reverberation and that different speech materials may differ in their robustness toward detrimental effects of reverberation.
Cluster of Excellence Hearing4all, Project Group Hearing, Speech and Audio Technology, Fraunhofer Institute for Digital Media Technology IDMT, D-26129 Oldenburg, Germany.
Jan
J
Rennies
Cluster of Excellence Hearing4all, Project Group Hearing, Speech and Audio Technology, Fraunhofer Institute for Digital Media Technology IDMT, D-26129 Oldenburg, Germany.
Henning
H
Schepker
Cluster of Excellence Hearing4all, Institute of Hearing Technology and Audiology, Jade University of Applied Sciences, Ofener Straße 16/19, D-26121 Oldenburg, Germany.
Inga
I
Holube
Cluster of Excellence Hearing4all, Medizinische Physik, Universität Oldenburg, 26111 Oldenburg, Germany.
Birger
B
Kollmeier
D000161:Acoustic Stimulation; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D009622:Noise; D059629:Signal-To-Noise Ratio; D013065:Speech Intelligibility; D013069:Speech Reception Threshold Test; D013997:Time Factors; D055815:Young Adult