The effect of a linked bilateral noise reduction processing on speech in noise performance

Authors

  • Jorge Meija National Acoustic Laboratories, Sydney, Australia; The Hearing Cooperative Research Centre, The University of Melbourne, Australia
  • Gitte Keidser National Acoustic Laboratories, Sydney, Australia; The Hearing Cooperative Research Centre, The University of Melbourne, Australia
  • Harvey Dillon National Acoustic Laboratories, Sydney, Australia; The Hearing Cooperative Research Centre, The University of Melbourne, Australia
  • Cong-Van Nguyen National Acoustic Laboratories, Sydney, Australia; The Hearing Cooperative Research Centre, The University of Melbourne, Australia
  • Earl Johnson The USA Department of Veterans Affairs, East Tennessee State University

Abstract

Directional processing already provides tangible noise reduction benefits in hearing aids but further improvement is needed for hearing-impaired listeners to communicate as effectively as normal-hearing listeners in noisy environments. The objective of this study was to investigate if a binaurally linked beamformer could further improve the signal-to-noise ratio (SNR). Speech reception thresholds (SRT) and spatial perception were compared for bilaterally fitted cardioid microphones and two binaurally linked beamformer processing conditions; 1) a single audio stream output to the two ears, and 2) two audio stream outputs which preserved spatial cues. 10 normal-hearing and 22 hearing-impaired listeners were recruited for this study. The strategies were implemented on a real-time PC processing platform, wired to a pair of behind-the-ear devices via a sound interface. A speech-in-noise test was administered using the Bamford-Kowal-Bench (BKB) sentences targeting the SNR for which 75% correct keywords were identified in spatially separated multi-talker babble noise and room reverberation. The SNR level at which the listeners acquired 95% intelligibility from continues speech discourse material, using a male and a female talker, was also obtained. Sound amplification was provided according to NAL-NL2. Both beamformer conditions improved the SRTs relative to the conventional cardioids, but by a greater degree for the hearing-impaired listeners, and more convincingly at the higher SRTs.

References

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Additional Files

Published

2011-12-15

How to Cite

Meija, J., Keidser, G., Dillon, H., Nguyen, C.-V., & Johnson, E. (2011). The effect of a linked bilateral noise reduction processing on speech in noise performance. Proceedings of the International Symposium on Auditory and Audiological Research, 3, 401–408. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2011-46

Issue

Vol. 3 (2011): Speech Perception and Auditory Disorders

Section

2011/4. Recent concepts in hearing-instrument processing and fitting

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