In very simple terms, digital and analogue refer to how the hearing aid amplifies and processes sound. Currently, digital technology is the most advanced available. Analogue technology is still manufactured by a small number of manufacturers but for the most part has been surpassed by digital technology.

both digital and analogue hearing aids comprise:

  a microphone, that picks up sound

  an amplifier that makes the sound louder and

  a receiver or loudspeaker, that delivers the amplified sound to the ear.

All hearing aids use batteries to power the electronic parts. Sound enters through a microphone. It is then processed, amplified and delivered to a receiver. The output from the receiver is sent either directly to your ear canal if you are wearing in-the-ear hearing aids, or via tubing if you are wearing behind-the-ear hearing aids.

Analogue technology has been in existence since the invention of the telephone. Analogue hearing aids amplify all sounds, soft and loud, by the same degree. This means that voices, background noise etc. are all made louder to the same level, which can be very annoying for some people. Minimal adjustments can be made but these hearing aids are not very flexible and can be limited in helping hearing.

With digital sound processing, the sound is registered mathematically. Sound is encoded as a series of numbers that measures its pitch and volume at a given instant in time. Processing the sound bit by bit is a much more precise method than previously used. The signal can be manipulated according to your hearing levels and listening needs. Digital sound has minimal distortion and, very importantly, has maximum flexibility, e.g. individual frequencies can be shaped to your hearing loss. Digital signal processing allows manufacturers to create hearing aids with enhanced processing and features thus helping a greater number of people who have a hearing loss than previously.