Objective: To determine common reference equivalent threshold sound pressure levels (RETSPL) for the earphones used in the extended high-frequency (EHF) range, as different earphones are commercially available, but there are not RETSPLs for each model.
Design: Hearing threshold sound pressure levels were measured up to 20 kHz for the Sennheiser HDA 200 audiometric earphone, and were compared to the ISO 389-5 (2006) norm and other investigations using that earphone and different ones.
Study sample: A total of 223 otologically-normal subjects (aged 5-25 years old) participated in the hearing determination.
Results: The results are in good agreement with previous studies of hearing thresholds using the same and other earphones.
Conclusions: The results of the present investigation are relevant for the international standard for the calibration of audiometric equipment in the 8 to 16 kHz frequency range, ISO 389-5. The data may be used for a future update of the RETSPL for circumaural and insert audiometric earphones.
Keywords: Pure-tone audiometry; aging; drug toxicity; high-frequency hearing loss; noise-induced hearing loss; presbycusis; sensorineural hearing loss; toxicity tests.