A hearing aid is an electronic device that amplifies and processes sound, and is worn to compensate for a hearing loss. Hearing aids come in different shapes and sizes. However, they all work in a similar way by delivering amplified sound to the ear. All hearing aids have a microphone to pick up sound and convert it to an electrical signal. This signal is then processed by a series of electrical components in an analogue hearing aid, or by a tiny ‘computer’ in a digital hearing aid. Most hearing aids are now digital. Once processed, the signals are finally passed to a receiver (earphone), or to a small vibrator that is worn against the bones behind your ear. This converts the electrical signal back to sound - ideally at a level that you can both hear and clearly understand.
A modern, digital "Behind the Ear" style hearing aid (Image © RNID)
Click here to read more about the different types of hearing aids available
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