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Differences between speech-shaped test stimuli in analyzing systems and the effect on measured hearing aid gain
Gitte Keidser1, Harvey Dillon, Elizabeth Convery
1National Acoustic Laboratories, Chatswood, NSW 2067, Australia. gitte.keidser@nal.gov.au
Ear and Hearing
|January 22, 2010
Summary
Spectral differences in hearing aid test stimuli can cause significant variations in measured gain, up to 8 dB. Careful selection of test signals is crucial for accurate hearing aid verification in nonlinear devices.
Area of Science:
- Audiology
- Acoustics
- Hearing Device Technology
Background:
- Accurate verification of hearing aid gain is essential for effective amplification.
- Nonlinear hearing aids require specific considerations for gain measurement.
- The choice of test stimulus can influence measurement outcomes.
Purpose of the Study:
- To investigate the impact of spectral variations among different test stimuli on hearing aid gain measurements.
- To quantify the potential discrepancies in gain verification due to stimulus differences in nonlinear hearing aids.
Main Methods:
- Spectra of nine distinct stimuli from five different analysis systems were acquired.
- Stimuli were analyzed to identify spectral characteristics relevant to hearing aid gain measurement.
Main Results:
- Most tested stimuli exhibited spectral characteristics aligning with one of two defined spectral profiles.
- The spectral differences between these two primary input spectra led to measured hearing aid gain variations as large as 8 dB.
Conclusions:
- The selection of appropriate test stimuli is critical for reliable and accurate hearing aid gain verification.
- Clinicians and researchers should be aware of the potential for spectral differences to introduce significant errors in gain measurements.
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