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Published on: March 24, 2023
Hearing aid saturation, coherence, and aided loudness discomfort
1Argosy Electronics, Minneapolis, Minnesota 55344.
Journal of the American Academy of Audiology
|March 1, 1992
Summary
Distortion in hearing aids can affect loudness perception and sound quality. This study found that hearing aid saturation-induced distortion impacts both, particularly in Class D devices with higher saturation levels.
Area of Science:
- Audiology
- Hearing Science
- Acoustics
Background:
- Hearing aid technology aims to improve audibility and sound quality.
- Saturation-induced distortion is a potential artifact in hearing aid amplification.
- Understanding distortion's impact on loudness perception is crucial for effective hearing aid fitting.
Purpose of the Study:
- To investigate the contribution of saturation-induced distortion to the sensation of loudness.
- To evaluate the effect of distortion on sound quality in hearing-impaired listeners.
- To compare distortion characteristics between Class A and Class D linear hearing aids.
Main Methods:
- Real-ear measurements of aided Loudness Discomfort Level (LDL) were performed.
- Five hearing-impaired listeners were fitted with Class A and Class D linear hearing aids.
- Real-ear coherence and sound quality judgments were used to assess saturation and distortion.
Main Results:
- Higher SPL, coherence, and sound quality ratings at LDL were observed for Class D hearing aids with high HFA SSPL90 compared to Class A aids with low HFA SSPL90.
- Saturation-induced distortion was found to influence both perceived loudness and sound quality.
- Results supported the hypothesis that distortion impacts loudness perception and sound quality.
Conclusions:
- Saturation-induced distortion plays a role in the perception of loudness and sound quality in hearing aid users.
- Hearing aid design, specifically the High-Frequency Saturation Sound Pressure Level (HFA SSPL90), influences distortion levels.
- Further research into managing distortion is recommended for optimizing hearing aid performance.
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