Equivalent hearing threshold levels for the RadioEar IP30 insert earphone and short-term stimuli: comparison of peak-equivalent and RMS-based measures.

To determine equivalent threshold sound pressure levels (ETSPL) for the RadioEar IP30 insert earphone for standardised short-term stimuli: IEC 60645-3 reference clicks and tonebursts in the frequency range from 250 Hz to 6 kHz, using the standardised peak-equivalent ETSPL procedure (peETSPL) and a new proposal based on the unweighted equivalent continuous sound pressure level of the periodically repeated short-term stimuli (ETSPL). Determination of peETSPL and ETSPL hearing threshold levels with otologically normal test subjects under the conditions given in ISO 389-9 using the standardised occluded-ear simulator according to IEC 60318-4. The study was based on tests with 25 subjects. The peETSPLs for the RadioEar IP30 insert earphone were compared with the respective reference threshold levels of the insert earphone ER-3A as standardised in the ISO 389 standards series. The ETSPL approach was tested by estimating the ETSPLs from the peRETSPLs and comparing the estimate with the direct results. Equivalent hearing threshold levels for standardised short-term stimuli for the RadioEar IP30 insert earphone were determined according to ISO 389-9 and given as both peETPSL and ETSPL. The RMS-based ETSPL approach turned out to be well applicable for the RadioEar IP30 insert earphone.