Spatial cue reproduction in modern receiver-in-the-ear hearing instruments

Authors

  • Fredrik Gran Global Research and Global Audiology, GN ReSound A/S
  • Jesper Rye Bønnelykke Global Research and Global Audiology, GN ReSound A/S
  • Astrid Haarstrup Global Research and Global Audiology, GN ReSound A/S
  • Jesper Udesen Global Research and Global Audiology, GN ReSound A/S
  • Todd Fortune Global Research and Global Audiology, GN ReSound A/S
  • Tobias Piechowiak Global Research and Global Audiology, GN ReSound A/S
  • Andrew Dittberner Global Research and Global Audiology, GN ReSound A/S

Abstract

This study investigates the ability to preserve spatial cues in receiver-in-the- ear (RIE) instruments for six different hearing aid manufacturers. In this particular study, the instruments were fitted bilaterally assuming a symmetric hearing loss profile. In cases where the manufacturer recommended a specific programming option to maximize spatial awareness, this option was chosen. Otherwise, the default mode was applied. S2 and N4 audiograms were used to mimic hearing-loss and testing was performed in an anechoic chamber on a KEMAR head. In order to mimic the peripheral filtering of the auditory system the left and right signals were filtered using a gammatone-filterbank. ILD's were estimated at the output of each band across angles from 0-360 degrees and compared to the corresponding values of the open-ear-response. ITDs were determined by low-pass filtering the left and right input signals and using a cross- correlation technique in order to find their respective time shift. Distortions of ILDs were as large as 10 – 15 dB for certain manufacturers whereas ITD distortions lay between 20-100 μs.

References

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Additional Files

Published

2011-12-15

How to Cite

Gran, F., Bønnelykke, J. R., Haarstrup, A., Udesen, J., Fortune, T., Piechowiak, T., & Dittberner, A. (2011). Spatial cue reproduction in modern receiver-in-the-ear hearing instruments. Proceedings of the International Symposium on Auditory and Audiological Research, 3, 441–448. Retrieved from http://proceedings.isaar.eu/index.php/isaarproc/article/view/2011-51

Issue

Section

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