Reference Equivalent Threshold Sound Pressure Levels for Insert Earphones

Abstract

Insert earphones, coupled to the ear canal by means of a long plastic tube and soft ear plug (Etymotic Research ER-3A Tubephone) are being used for a number of audiometric applications as an alternative to supra-aural earphones. This report presents the results of hearing threshold level measurements in 36 ears of young, otologically normal listeners. The results are expressed as mean sound pressure levels measured on a 2 cm¹ coupler according to IEC 126 as well as on an ear simulator according to IEC 711.