Hearing Aid Technology

In all hearing aids, sound enters through a microphone. It is then processed, amplified and delivered to a receiver (loudspeaker). This sends the output either directly to the user’s ear canal, via tubing to an earmould and into the ear canal, or via a thin wire to a receiver placed directly in the ear.

There are two types of sound processing: Analogue and digital.

Analogue sound processing

In analogue instruments, sound is processed as an electrical signal by a microphone.  Analogue sound is like making a photocopy; the sound is registered and you get an overall picture. But the actual processing is like recopying a photocopy – it can only be done to a certain extent because it causes a deterioration of the original imprint.

Digital sound processing

In a digital hearing aid the acoustic signal is converted into digits (0, 1), processed within the hearing aid, and then reconverted to an analogue acoustic signal for the listener. A digital signal can be repeated endlessly without affecting the overall quality. It’s like making copies of a scanned image: each copy is a perfect duplicate of the original.

Copyright 2010 Oticon A/S. All rights reserved.