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How to get the best hearing aid

Hearing aid features explained

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Hearing aid features explained

Discover the hearing aid features that could make your life easier - and the ones you shouldn't waste your money on.

Hearing aids all contain essential parts, such as a microphone, amplifier, receiver (speaker), volume control and battery - but what about the other features on offer? Our A-Z jargon buster explains the most common terms you'll come across.

While advanced features can sound exciting, remember that they can also make your hearing aids more expensive and complicated than necessary. Whether you need additional features depends on your lifestyle and type of hearing loss.

The audiologist should assess your needs and be able to advise on the features that might suit you, based on your lifestyle and level of hearing loss. They should then recommend the best brand and model of hearing aid for you.

Once you've got an idea of what you need, our guide to hearing aid prices will show you how much you can expect to pay for the level of hearing aid you want.

A-Z of hearing aid features

Anti-phase feedback

Detects whistling and cancels out feedback.

Automatic adaptation

The aid adjusts itself (rather than the audiologist doing it) as you get used to wearing it.

Automatic compression

This provides more amplification for low sound levels than high ones, preventing high sound levels from being intrusively loud.

Automatic noise detection/reduction

This is a common feature present in most hearing aids and it can reduce irritating background noise, such as the clinking of dishes.

Bands or channels

Most hearing aids divide the frequency range they support into bands or channels as a means of fine-tuning the hearing aid for the individual, making speech clearer and suppressing background noise. More channels or bands can enable better tracking of the hearing loss pattern, if this is what you need.  However, more bands doesn’t necessarily mean improved sound quality.

Bluetooth and direct audio input

Direct audio input (DAI) is a way for a hearing aid to connect directly to other external audio sources, such as CD players, MP3 players, mobile phones or assistive listening devices. Direct audio input connection can be either through a wire connecting to the ‘shoe’ (a little piece that connects to the bottom of the hearing aid) or it can be wireless, via Bluetooth.

Bluetooth technology also allows co-ordination between two hearing aids, resulting in improved speech audibility.

Choice of listening programs

Many digital hearing aids allow you to switch between various settings for different listening conditions, and some adjust automatically. The telecoil setting (see below) can be added as a program.

Control gain

You can adjust the amplification of certain sounds – for example, reduce traffic noise but still be able to hear birds.

Directional microphone

This is found in most hearing aids. It can be switched on to pick up sounds in front of you, so you can hear them better than sounds behind or to the side of you. This makes it easier for you to focus on what you want to listen to in a noisy place.

Many hearing aids automatically detect where the unwanted noise is coming from and adjust the microphone to reduce it. However, hearing aids won’t know what you want to listen to, and so the reduction of unwanted sound can never be perfect.

Low-battery indicator

A common feature, present in most hearing aids, that alerts you when it’s time to change batteries.

Telecoil (also known as a loop)

You may have spotted the sign indicating a loop system, known as Telecoil, in banks or shops. Provided it’s working and switched on, it will enable you to hear more clearly in places with lots of background noise. You can also use Telecoil with telephones and mobile phones, but they must be hearing aid-compatible.

Most hearing aids have a Telecoil setting but you may need to get it activated by your audiologist first.

User-defined settings

Allows you to control how the device behaves.


These are tiny tunnels in earmoulds that help minimise the blocked sensation you can get from wearing something in your ears. Whether they are present usually depends on how well you hear low-frequency sounds.

Wax guard or trap

This helps keep the aid free of ear wax, which can cause problems.

Using your hearing aid with other technologies

Hearing aids and mobile phones/smartphones

Whether you have a corded or cordless (DECT) home phone, mobile or smartphone, it is likely you can use it with your hearing aid. First try it on your hearing aid's M (microphone) setting. This should amplify the conversation without introducing acoustic feedback (a howling or whistling sound). On some phones you can increase the volume rather than adjusting your hearing aid.

Switching to the Telecoil/hearing loop setting should improve the clarity, but some mobiles and smartphones may cause interference that you’ll hear as a buzzing sound.

Try using a Bluetooth neckloop paired to your phone, or if you’re thinking of getting a new mobile or smartphone, look out for one that has a T4/T3 and M4/M3 hearing aid compatibility rating, which should mean little - if any - buzz. 

You can discuss these options with your audiologist, who should refer you on for more information - for example, to a hearing therapist who can advise on this type of equipment.

For more information about managing your hearing and hearing-compatible products, contact the Action on Hearing Loss information line on 0808 808 0123 (freephone).

How long do hearing aids last?

It's up to you how often you have your hearing assessed and your hearing aids upgraded, but we'd suggest doing it at least once a year. However, when you’re buying privately this comes at a cost.

Hearing aids should typically last three to five years, so you’ll need to budget for buying new ones. You’ll also need to factor in the cost of replacing parts, such as batteries and wax traps.

It's likely that your hearing loss will change over time. On average, hearing will deteriorate by five decibels a year, so if you notice any deterioration or feel your hearing aids aren’t working so well, seek advice from your audiologist. They should be seeing you at follow-up appointments, so your hearing aids can be reprogrammed if your hearing deteriorates.