Article ID: e25.78
An ISO standard on the reference equivalent threshold sound pressure levels for circumaural earphones was established in 2004. This international standard enabled the use of circumaural earphones for pure-tone audiometry, along with supra-aural earphones, which had long been used. However, some reports describe that the hearing threshold levels obtained using supra-aural earphones and circumaural earphones did not always agree even when the same subjects were tested under identical measurement conditions. Clinicians might become confused by this disagreement when the use of circumaural earphones becomes popular. In this study, we examined subjects by pure-tone audiometry using several earphones of both types and an identical measurement procedure. On the basis of the measurement results, the expected amount of threshold difference relative to reference circumaural earphones was calculated for supra-aural earphones of each model.
