摘要 |
The present invention provides an apparatus (100) for determining in situ the acoustic seal provided by an in-ear device (10) of a hearing protection/aid nature inserted into the ear canal (20) of an individual. The device (10) having a sound bore (12) with an environment opening (13) and an ear opening (14) outside and inside the ear canal (20) respectively. The apparatus (100) includes a sound measurement device (41) that removably engages the environment opening (13), a probe microphone (42) and a reference microphone (44) isolated from each other and connected to a data processing unit (50) having a control box (52) and a speaker (51). Both microphones (42, 44) measure sound pressure levels (P3', P2') inside said ear canal (20) and outside in close proximity of the device (10) respectively, the sound pressure levels (P3' P2') corresponding to a known noise signal created by the speaker (51). The data processing unit (50) records and processes the sound pressure levels (P3', P2') to provide a corresponding calculated value of a sound pressure level difference provided by the device (10). |