IEC 60318-8:20 22描述了一种声学耦合器，用于在测试助听器或插入式耳机的声学性能时，在高达16kHz的频率范围内，以指定的声阻抗加载助听器或插入式耳机。它适用于通过耳塞、耳模或类似装置耦合到耳朵的空气传导助听器和耳机。 声学耦合器不模拟人耳。然而，它的有效体积仅为0.4 cm3，小到足以在低于16kHz的频率范围内不会在耦合器中产生显著的共振。因此，它将为耳机加载已知的声阻抗，这允许在扩展高频测听中使用的耳机上获得低不确定性的可重复测量。

IEC 60318-8:2022 describes an acoustic coupler for loading a hearing aid or insert earphone with a specified acoustic impedance when testing its acoustic performance, in the frequency range up to 16 kHz. It is suitable for air-conduction hearing aids and earphones, coupled to the ear by means of ear inserts, earmoulds or similar devices.
The acoustic coupler does not simulate the human ear. However, it has an effective volume of only 0,4 cm³, which is small enough not to produce significant resonances in the coupler in the frequency range below 16 kHz. Therefore, it will load the earphone with a known acoustic impedance, which allows repeatable measurements with low uncertainty to be obtained on earphones used in extended high-frequency audiometry.