How hearing aids work
Modern hearing aids are small, but they are doing a lot of clever work behind the scenes. A hearing aid picks up sound, cleans it up and makes it clearer, then delivers it into your ear, all in a fraction of a second.
The four main parts.
Every hearing aid, whatever the brand, is built around four parts working together.
Picks up sound from around you and turns it into an electrical signal.
The brain of the hearing aid. Analyses the sound, reduces background noise, and shapes it to match your specific hearing loss.
Turns the processed signal back into sound and delivers it into your ear.
Powers everything, either rechargeable or a disposable battery, depending on your hearing aid.
From sound to hearing, in milliseconds.
This whole process repeats thousands of times a second, continuously adjusting to what is around you.
The microphone picks it up.
Cleaned up and shaped to you.
Sent into your ear as sound.
Clearer, and matched to your hearing.
What modern hearing aids can also do.
A simple amplifier makes everything louder, including background noise. A modern processor is smarter.
Modern hearing aids double as wireless earphones, with sound shaped to your hearing loss. Bluetooth hearing aids.
The newest models use AI chips to pull speech out of a noisy room rather than just turning the background down. See our brands.
Volume, programmes and fine-tuning from an app, and remote adjustments from us where appropriate.
Rechargeable models give a full day of hearing from an overnight charge, no fiddly batteries. Rechargeable hearing aids.
Set up for you.
Hearing aids cannot fully restore hearing to what it was, but they make sound clearer and easier to understand. Your audiologist programmes yours from your hearing test results, then fine-tunes it at your fitting and follow-up appointments, so it is matched to your hearing rather than a generic setting.
In our clinic, or in your home.
Same audiologists, same equipment, same full assessment. You choose where.
The full assessment at our Birmingham clinic, completely free, no obligation.
- 60 minutes, results before you leave
- Evening and weekend appointments
- Bring someone, they are tested free too
The same full test, brought to your living room, tuned to real life: your TV, your phone, your front door.
- Same audiologists, in the comfort of your home
- Whoever is with you is tested free
- Birmingham, Solihull, Coventry and more
Common questions.
An amplifier makes everything louder by the same amount. A hearing aid is set up to your own hearing test, so it adds more where you have lost more, and leaves alone the sounds you still hear well. That is why an amplifier makes a noisy room unbearable and a hearing aid does not.
No, and anyone who promises that is overselling. They make up for the hearing you have lost rather than repair it. What most people get back is being able to hold a conversation again in the places that matter to them.
Usually four to six years of daily wear. They sit in a warm, damp ear all day, which is hard on electronics. Regular servicing, which is included with yours, makes a real difference to how long they last.
A few weeks for most people. The first few days are the strangest, because sounds you had stopped hearing all come back at once: your own voice, the kettle, your own footsteps. That settles down. We book follow-up appointments through that period rather than leaving you to it.
Written and clinically reviewed by our HCPC registered audiologists. Last reviewed: 14 September 2026. This page is general information, not a diagnosis. If you are worried about your hearing, book a hearing test or speak to your GP.