The inspection system for hearing aids in situ working condition

With the increase of population and aging trend, more and more people are disabled in hearing. Hearing aid is a special amplifier to help the hearing disabled. The quality of hearing aids is important to the disabled physical and mental health. According to the international standard IEC 60118-0, some general parameters of the hearing aid have been measured to evaluate the quality. Because of taking into account the acoustical influence of the wearer on the performance of hearing aids, this paper establishes a system which is based on the standard IEC 60118-8 to automatically measure the performance characteristics of hearing aids under simulated in situ working condition. There are some parameters that are considered important for the evaluation of the performance of hearing aids as normally worn, such as full-on insertion gain, insertion frequency response and directional characteristics. This paper describes the methods to measure these parameters and establishes a platform to inspect them. Meanwhile, the inspection data can be processed and recorded automatically. A hearing aid is selected to do the experiments. The experiment results show that the system can be competent for inspection the performance of hearing aids in situ working condition.