Speech intelligibility with binaurally linked hearing aids


  • Iris Arweiler Centre for Applied Hearing Research, Technical University of Denmark, DK-2800 Lyngby, Denmark
  • Jörg M. Buchholz Department of Linguistics, Faculty of Human Sciences, Macquarie University, NSW-2190, Australia and National Acoustic Laboratories, NSW-2067 Chatswood, Australia
  • Torsten Dau Centre for Applied Hearing Research, Technical University of Denmark, DK-2800 Lyngby, Denmark


Conventional compression algorithms in bilateral hearing-aid fittings distort the interaural level differences (ILD’s) due to independent gain characteristics at the two ears. By transmitting signals between hearing aids, the compression can be coordinated and the same gain can be applied to both ears, thus preserving the ILD’s. The present study investigated the influence of such “binaurally linked” hearing aids on speech intelligibility. Hearing-impaired listeners with a symmetric hearing loss were fitted with hearing aids connected to a hearing aid research platform (HARP). Speech reception thresholds (SRT’s) were measured in a loudspeaker setup with the target speech and the masker spatially separated. Slightly, but not significantly better SRT’s were achieved when the hearing aids were binaurally linked and combined with slow compression than when unlinked fast compression was used. The difference between monaural and binaural speech intelligibility was independent of the hearing aid algorithm. Thus, the preservation of the exact ILD information does not seem to be critical for binaural processing and speech intelligibility in the considered conditions.


Behrens, T. (2008). “Spatial hearing in complex sound environments.” Hear. Rev. 15, 94–102.

Bentler, R. A., Pavlovic, C. V. (1989). “Transfer functions and correction factors used in hearing aid evaluation and research.” Ear Hear. 10, 58–63.

Brand, T., Kollmeier, B. (2002). “Efficient adaptive procedures for threshold and concurrent slope estimates for psychophysics and speech intelligibility tests.” J. Acoust. Soc. Am. 111, 2801–2810.

Bronkhorst, A. W. and Plomp, R. (1988). “The effect of head-induced interaural time and level differences on speech intelligibility in noise.” J. Acoust. Soc. Am. 83, 1508–1516.

Dillon, H. (2001). Hearing aids. New York: Thieme, pp. 379–380.
Keidser, G., Rohrseitz, K., Hamacher, V., Carter, L., Rass, U., Convery, E. (2006). “The effect of multi-channel wide dynamic range compression, noise reduction, and the directional microphone on horizontal localization performance in hearing aid wearers.” Int. J. Audiol. 45, 563–579.

Moore, B. C. J., Johnson, J. S., Clark, T. M., Pluvinage, V. (1992). “Evaluation of a dual-channel full dynamic range compression system for people with sensorineural hearing loss.” Ear Hear. 13, 349–370.

Musa-Shufani, S., Walger, M., von Wedel, H., Meister, H. (2006). “Influence of dynamic compression on directional hearing in the horizontal plane.” Ear Hear. 27, 279–285.

Noble, W., Byrne, D., Ter-Horst, K. (1997). “Auditory localization, detection of spatial separateness and speech hearing in noise by hearing impaired listeners.” J. Acoust. Soc. Am. 102, 2343–2352.

Shinn-Cunningham, B. G. (2003). “Spatial hearing advantages in everyday environments.” Proceedings of the ONR workshop on Attention, Perception, and Modeling for Complex Displays. Troy, NY.

Sockalingam, R., Holmberg, M., Eneroth, K., Schulte, M., (2009). “Binaural hearing aid communication shown to improve sound quality and localization.” Hear. J. 62, 46–47.

Wagener, K., Josvassen, J. L., Ardenkjaer, R. (2003). “Design, optimization and evaluation of a Danish sentence test in noise.” Int J Audiol, 42, 10–17.




How to Cite

Arweiler, I., Buchholz, J. M., & Dau, T. (2011). Speech intelligibility with binaurally linked hearing aids. Proceedings of the International Symposium on Auditory and Audiological Research, 3, 65–72. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2011-07



2011/1. Indicators of hearing impairment and measures of speech perception