You may have heard hearing aids being described as either ‘analogue’ or ‘digital’ and you may well wonder how hearing aids work. A common misconception is that digital hearing aids are in-the-ear (ITE) hearing aids. Both types of hearing aids come in different sizes and styles; the difference between them is in the way that they process sound and the individual benefits that they offer.
|Digital hearing aids||Analogue hearing aids|
|Use a tiny computer to process sound into ‘bits’ of data/numbers that can be manipulated by a small computer in the hearing aid.||Use conventional electronics to convert sound into electrical signals that are amplified and passed to the earphone on the hearing aid.|
|Can be programmed to suit your particular type and ‘shape’ of hearing loss (frequency specific amplification). Thus possible to tailor and process sounds very precisely, even if there are changes in hearing thresholds.||Not all can be programmed to suit type and 'shape' of hearing loss.|
|Can be programmed to suit each person’s hearing loss in different environments.||Some are programmable for different environments.|
|Suppress background noise so that speech is easier to hear and understand especially in noisy environments. Note: This does not necessarily help the patient to pick out a single voice from other sounds in a noisy environment, especially when several people are talking.||Make sounds louder but may not discriminate between them.|
Note: Even though we fit digital hearing aids with the most advanced technology available on the NHS at present, we must emphasise that there are limitations. It is well known that sensorineural hearing loss causes irreversible damage to the cochlea/nerve, thus frequency specific discrimination may also be permanently impaired.
In essence hearing aids will aid the residual hearing, but cannot restore/normalise the hearing function.