How do hearing aids work?

How do hearing aids actually work? What makes them so effective at helping people with hearing loss hear more clearly and naturally? These are really important questions that most people will ask when thinking about getting their first hearing aids.

Let’s explore how modern technology transforms a hearing aid into so much more than just an amplifier with a loudspeaker attached.

All modern hearing aids still feature these essential components:

  • Microphones
  • Amplifier
  • Computer chip
  • Loudspeaker
  • Battery

In simple terms, the microphone picks up sounds, the computer chip processes those sounds and sends the signals on to the amplifier. The amplifier makes those sound signals stronger and passes them onto the speakers, which then transmit those sounds to the ear canal. From the ear canal, the sounds travel as electrical impulses to the brain for processing.

It sounds so simple doesn’t it? So, how do these 5 components work to help you hear better and why are modern hearing aids simply the best solution for most hearing loss problems?

Microphones–sensitive and subtle

The microphone transforms sounds into electrical signals and passes those signals on to the amplifier. Older analogue hearing aids picked up and amplified all sounds equally. This made hearing in many everyday situations, such as listening to a conversation in a crowd or locating a specific sound, extremely difficult.

Modern microphones are so much more sensitive and powerful than the early models and the development of directional microphones is a particularly important innovation. Directional microphones allow you to focus your listening in specific areas and cut out background noise. This makes it much easier to hear the people talking to you without amplifying other distracting noises.

Many hearing aids can connect wirelessly to external microphones and provide a direct connection to the speaker in settings such as meetings, conferences and classrooms. Phonak, for example, offer the exciting range of Roger microphones that offer a 61% improvement in understanding against background noise.

Directional microphones and binaural processing also help you locate sounds more accurately. This means you no longer have to put up with that bewildering and exhausting struggle to work out where the sounds are coming from.

Amplifier—more power to your ears

The traditional analogue hearing aid amplified sound simply by making the sound waves bigger. Unfortunately, this made all sounds louder including the unwanted sounds.

Modern digital hearing aids can modify the sound in many more subtle ways to provide sound that is much more natural as well as make listening easier in noisy settings. In digital hearing aids, this amplification and sound processing takes place in the computer chip.

Minimal power requirements, low sound distortion rates, and small size are typical characteristics for modern hearing aid amplifiers. This means you can enjoy hearing aids that are powerful, flexible and yet nearly invisible.

Computer chip—millions of calculations per second

The miniature computer chip is the heart of the modern hearing aid. These mini-computer chips make around 40 million calculations each second as they process the incoming signals and help you make sense of the sounds around you.

The computer chips provide an incredibly fine degree of control over which sounds to emphasise and which to reduce. For example, they can recognise that you’re in a restaurant and help filter out the sounds of cutlery or dishes while amplifying the frequencies where most speech sounds take place.

You could say it’s a little bit like the graphic equalizer on a sound system. This multi-channel processing significantly improves speech comprehension and hearing against background noise.

Mostly, automation takes care of the enormous range of calculations but some hearing aid models allow you to fully customise the settings. Some digital processing chips, such as those in the Widex Evoke, are actually learning from the way you respond and will remember your choices.

The digital computer chip also provides superior feedback control. Feedback is that whistling sound that tended to occur on older hearing aid models when the microphone picked up amplified sound and created an amplified sound loop. Enormously powerful computer chips can analyse these sounds and respond instantly to safeguard your ears from feedback.

This type of technology can also help with wind noise reduction and tinnitus management. Many premium hearing aid models offer some form of white noise masking to reduce the impact of severe tinnitus.

Wireless and Bluetooth connectivity provide direct from source sound whether you’re on the phone, listening to music, or watching a film. This connectivity allows the signal to bypass much of the background noise so you can enjoy clear sound transmission directly to your ears.

Loudspeaker—natural sound

Finally, the loudspeaker (or receiver) delivers the processed signals as acoustic sound to your inner ear. Modern receivers offer enormous design improvements over earlier models including greater robustness, more comfortable ergonomic design, and more effective performance.

A range of styles from completely in the canal to behind-the-ear provide different options to suit a range of personal needs. Some of these options that sit in the ear actually help reduce feedback or wind noise due to the firm seal they form in the ear canal.

Battery—the powerhouse

Of course, the battery powers all of this amazing technology. Technical advances in battery design mean that modern hearing aids can be more powerful, more reliable and yet smaller and more comfortable. You no longer need to struggle with the frequent removal of fiddly little batteries and their replacement.

Many hearing aids, such as the Oticon OPN hearing aids feature rechargeable batteries that make recharging a breeze. Simply place your hearing aid in the rechargeable dock and rapid overnight charging means your hearing aids are ready to go again the next morning.

Phonak’s Lyric hearing aid delivers 24/7 performance for months at a time without any need to remove the hearing aid for battery charging or replacement.

Modern hearing aids are extraordinarily effective and can transform your life. If you have hearing loss, don’t delay; talk to your House of Hearing audiologist about how hearing aids can work for you.