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High-frequency audiometry. Masking in electric bone-conduction audiometry.

H Löppönen
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Abstract

Recently, the 'electric bone-conduction' (EBC) audiometer (Audimax 500) has been used to measure high-frequency (HF) hearing. With this audiometer stimulation is binaural. No commercial masking method was available. In this study, white noise from a Madsen OB822 audiometer and presented via Sony MDR-V4 dynamic earphones, was used for masking. The masking and cross-hearing effect was measured in 8 unilaterally deaf subjects and the masking procedure was tested with 104 young normal-hearing subjects. The results showed that the EBC signals can be masked with air-conduction signals, and thus, the EBC measurements reflect monaural thresholds. The minimum masking level was 50-60 dB SPL in the HF range. There were no cross-hearing problems in the HF range with the earphones used. At the frequencies 0.5-14 kHz, the better ear's masked EBC thresholds were on the average 2.6 dB (range 0-4.5 dB) poorer, compared with the binaural EBC thresholds, indicating a binaural summation effect.

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Acoustic StimulationAdolescentAdultAmplifiers, ElectronicAudiometryAuditory ThresholdBone ConductionChildEquipment DesignFemaleHearingHumansMaleNoisePerceptual MaskingJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

H Löppönen. 1992. High-frequency audiometry. Masking in electric bone-conduction audiometry.. https://doi.org/10.3109/01050399209045979

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