| 摘要 |
A method and apparatus for objectively assessing acoustical performance of an in-ear device having a passageway extending there through use a dual microphone probe that removably engages the passageway. The acoustical performance of the in-ear device is performed with the in-ear device inserted into the ear canal of the user and a reference sound source. A clip holding the probe in an acoustic near field of the sound source permits real time calibration thereof. The method and apparatus allow on-site and in-situ measurement of a predicted personal attenuation rating (P-PAR) of the device, a subject-fit reinsertion test, an acoustic seal test, a rating test, a stability and reliability test , as well as a protection test of the device with an assessment of a filtered predicted exposure level (F-PEL) at the ear for a specific noise exposure level. The apparatus may be simply housed along with the sound source for in-field evaluation tests. |
