Section 8 of IEC 6031 delineates the use of an acoustic coupler for loading an earphone or hearing aid with a predetermined acoustic impedance, which is essential for assessing the device’s physical performance characteristics. This coupler is effective across the frequency range of 125 Hz to 8 kHz. It is designed for use with air-conduction hearing aids and earphones, which are connected to the ear via ear inserts, such as ear molds or comparable devices.
It is important to note that the sound pressure produced by an earphone is typically not uniform between the coupler and a person’s ear. Nonetheless, the coupler serves as a straightforward and readily accessible tool for exchanging specifications and physical data related to hearing aids. Additionally, it is utilized for calibrating the specified insert earphones that are commonly used in audiometric testing.
