Influence of noise type on speech reception thresholds across four languages measured with matrix sentence tests

Abstract

Objective: To compare speech reception thresholds (SRTs) in noise using matrix sentence tests in four languages: German, Spanish, Russian, Polish. Design: The four tests were composed of equivalent five-word sentences and were all designed and optimized using the same principles. Six stationary speech-shaped noises and three non-stationary noises were used as maskers. Study sample: Forty native listeners with normal hearing: 10 for each language. Results: SRTs were about 3 dB higher for the German and Spanish tests than for the Russian and Polish tests when stationary noise was used that matched the long-term frequency spectrum of the respective speech test materials. This general SRT difference was also observed for the other stationary noises. The within-test variability across noise conditions differed between languages. About 56% of the observed variance was predicted by the speech intelligibility index. The observed SRT benefit in fluctuating noise was similar for all tests, with a slightly smaller benefit for the Spanish test. Conclusions: Of the stationary noises employed, noise with the same spectrum as the speech yielded the best masking. SRT differences across languages and noises could be attributed in part to spectral differences. These findings provide the feasibility and limits of comparing audiological results across languages.

Key Words::

• Speech reception threshold (SRT)
• matrix sentence test
• intelligibility
• German
• Spanish
• Russian
• Polish
• speech intelligibility index (SII)
• stationary noise
• fluctuating noise
• multitalker babble

Acknowledgements

This work was supported by the European Regional Development Fund (ERDF), project: HurDig; and by the Deutsche Forschungsgemeinschaft (EXC 1077 Hearing4all). We especially thank Jan Rennies for his very helpful comments on earlier versions of this manuscript and for providing the Fraunhofer SIP Toolbox which was used to calculate the SII.

Notes

Declaration of interest: The authors report no conflicts of interest. Birger Kollmeier is affiliated with H rTech gGmbH, non-profit institution, that owns copyrights of the used tests.

Supplementary material available online

Supplementary Table A1 available online at http://informahealthcare.com/doi/abs/10.3109/14992027.2015.1046502.

Notes

1. All SII predictions were done using the SIP Toolbox provided by Fraunhofer IDMT, which includes an implementation of the SII according to ANSI-3.5 1997.

2. The same statistical analysis was also applied to SRT differences between SRTs in ICRA1m (as a possible reference noise across languages) and SRTs measured in the other stationary noise conditions revealing highly significant main effects for both factors and their interaction. This indicates that there is no single language-specific correction that would help to reduce the language difference across all noise conditions to a single, noise-specific correction applicable in the same way to all languages.