Click-evoked auditory brain stem responses (ABRs) were measured using a Beyer DT48 circumaural earphone and an Etymotic ER-3A insert earphone in a group of normal-hearing subjects. Comparisons were made between time waveforms and amplitude spectra for the two transducers. ABR waveforms, latencies, and thresholds were compared for the two transducers. Click-evoked ABR and behavioral thresholds were comparable for the two earphones. In addition, absolute response-component latencies differed by an amount that was equivalent to the travel time introduced by the insert earphone's sound-delivery tube. Inter-peak latency differences were virtually identical. These findings suggest that the insert earphone is a viable transducer for clinical ABR evaluations. Further, a temporal correction may be all that is necessary to account for the difference between the insert earphone and the circumaural earphone if other characteristics of the transducers are similar.
ASJC Scopus subject areas
- Speech and Hearing