Communication Acoustics: An Introduction to Speech, Audio and Psychoacoustics

19Technical Audiology

The enhancement of degraded hearing has been around for a long time. The simplest acoustic device used for hearing enhancement is an ear trumpet. An ear trumpet is a horn that collects sound at its large opening and transmits it to the ear, thus amplifying sound, especially from the direction in which the horn is pointing. When the electronic amplification of sound was invented, it was applied to hearing enhancement. However, it was not until the invention of the transistor and miniaturization of devices that hearing instruments became practical. Microprocessors and digital signal processing have introduced new possibilities to enhance the performance of hearing instruments. Modern electronics have also been a prerequisite for the development of cochlear implants, in which a major part of the peripheral auditory system is bypassed and sound information is fed electronically to the auditory nerve. It would be reasonable to assume that in the future even more complex means will be developed for the enhancement of degraded hearing.

Electronic technology has also enabled better methods for testing hearing performance. Tuning forks or live speech and whisper sounds may still be used to get a rough estimate of whether the auditory system is functioning in general. However, more advanced methods are needed for more accurate information on hearing performance.

Audiology is a branch of medical science and physiology that studies hearing, balance, and disorders related ...