DESIGN AND STUDY SAMPLE: Study 1 determined ETSPL values in 25 normal-hearing subjects aged 18-25 years at seven test frequencies (500-8000 Hz). Study 2 assessed the intra- and inter-session test-retest threshold reliability in a separate group of 50 adult subjects.
RESULTS: The ETSPL values for the consumer IE deviated from the reference values for audiometric IEs, with the largest differences (7-9 dB) observed at 500 Hz across ear tips. This is likely related to shallow tip insertions. However, test-retest threshold variations were comparable to those reported for audiometric transducers.
CONCLUSIONS: Ear tip-specific corrections to the reference thresholds in the standards are required for calibration of consumer IEs used in low-cost audiometry when their ear tips only allow superficial insertion into the ear canal.