The influence of hearing-aid microphone location and room reverberation on better-ear effects

Authors

  • Tobias Neher Eriksholm Research Centre, Oticon A/S, Kongevejen 243, DK-3070 Snekkersten, Denmark
  • Claudia Breitsprecher Institute of Hearing Technology and Audiology, University of Applied Sciences Oldenburg, Ofener Str. 16, D-26121 Oldenburg, Germany
  • Søren Laugesen Eriksholm Research Centre, Oticon A/S, Kongevejen 243, DK-3070 Snekkersten, Denmark

Abstract

This study quantified the in uence of hearing-aid microphone location and room reverberation on so-called better-ear effects (BEEs), i.e. the ear- specific signal-to-noise ratio (SNR) changes brought about by head and pinna ltering in situations with spatially separated sound sources. Using an acoustic manikin, BEEs were measured for various target-masker constellations and for two microphone locations: above the outer ear (BTE) and at the ear-canal entrance (CIC). To determine the effects of reverberation, all measurements were made under anechoic and reverberant conditions. Compared to the CIC position, the BTE position led to substantially lower high-frequency SNRs on the side of the masker when the target was in front and the masker to the side or the rear of the manikin. Furthermore, even though BEEs were found to decrease as the ratio of reverberant to direct sound increased, considerable BEEs remained even under fairly extreme reverberant conditions. Altogether, these results demonstrate that, relative to the BTE position, hearing-aid microphones located at the ear-canal entrance are advantageous as far as head and outer-ear induced SNR changes are concerned. In addition, they indicate that BEEs of a noteworthy magnitude should be available in the reverberant listening situations experienced by typical hearing-aid users.

References

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Additional Files

Published

2009-12-15

How to Cite

Neher, T., Breitsprecher, C., & Laugesen, S. (2009). The influence of hearing-aid microphone location and room reverberation on better-ear effects. Proceedings of the International Symposium on Auditory and Audiological Research, 2, 505–512. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2009-52

Issue

Vol. 2 (2009): Binaural Processing and Spatial Hearing

Section

2009/4. Recent concepts in binaural cochlear-implant and hearing-aid processing

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