Degradation of spatial sound by the hearing aid

Authors

  • Jesper Udesen GN ReSound A/S, Ballerup, Denmark
  • Tobias Piechowiak GN ReSound A/S, Ballerup, Denmark
  • Fredrik Gran GN ReSound A/S, Ballerup, Denmark
  • Andrew B. Dittberner GN ReSound North America, Bloomington, MN, USA

Abstract

It is well known that the hearing aid distorts the spatial cues used to localize sound sources and this has severe consequences for sound localization and for listening in noise. However, it is not clear how the different components in the hearing aid contribute to the degradation of spatial sound. In this study we investigate how the spatial sound is degraded by four hearing aid components: 1) the microphone location, 2) the directionality (beamforming), 3) the compressor, 4) the real ear measurement. Head Related Transfer Functions from an artificial KEMAR head are convolved with appropriate excitation sounds and processed through the respective hearing aid algorithm. The performance metrics under investigation are: 1) interaural level difference (ILD), 2) interaural time difference (ITD), 3) monaural spectral cues. It is found that the main source for ILD degradation is the position of the microphone around the pinna which distorts the ILD by up to 30 dB. It is also found that the real ear measurement compensation severely affects the monaural spectral cues.

References

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Hawley, M.L., Litovsky, R.Y., and Colburn, H.S. (1999). “Speech intelligibility and localization in a multi-source environment,” J. Acoust. Soc. Am., 105, 3436-3448.

Van den Bogaert, T., Klasen, T.J., Moonen, M., Van Deun, L., and Wouters, J. (2006). “Horizontal localization with bilateral hearing aids: Without is better than with,” J. Acoust. Soc. Am., 119, 515-526.

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Published

2013-12-15

How to Cite

Udesen, J., Piechowiak, T., Gran, F., & Dittberner, A. B. (2013). Degradation of spatial sound by the hearing aid. Proceedings of the International Symposium on Auditory and Audiological Research, 4, 271–278. Retrieved from http://proceedings.isaar.eu/index.php/isaarproc/article/view/2013-29

Issue

Section

2013/5. Design and evaluation of hearing-aid signal processing