Interaural attenuation for tubephone insert earphones.
Interaural attenuation of pure tone and speech signals was evaluated for a new audiometric insert earphone, the ER-3A tubephone, and a conventional TDH-49P supra-aural earphone in seven unilaterally deaf adult subjects. These results validate and extend the interaural attenuation data reported by the manufacturer of the ER-3A and his associates. At frequencies of 0.5 to 1 kHz, mean interaural attenuation for the deeply inserted ER-3A decreased from 94+ dB to 81 dB, with the lowest value for any subject, 75 dB. Interaural attenuation for speech approximated that of the 1 to 2 kHz frequency range. The ER-3A tubephone provides significantly greater acoustic isolation between the two ears in the low-mid frequency audiometric range than the conventional supra-aural earphone.
Sklare
D A
DA
Clinical Audiology, National Institutes of Health, Bethesda, Maryland.
Denenberg
L J
LJ
D000328:Adult; D001299:Audiometry; D006310:Hearing Aids; D006801:Humans; D008297:Male; D008875:Middle Aged; D014159:Transducers