How do modern hearing aids work?

Modern hearing aids are now powerful computers, which, thanks to the latest technology, can be perfectly adapted to individual needs. As well as being extremely comfortable to wear, they also come in attractive designs.

They are usually made up of three main components: A microphone, a processor, and a loudspeaker. The microphone picks up sounds, or acoustic signals, from the environment and transmits them to the processor. The processor amplifies the sounds and converts them into electrical signals. The loudspeaker, or receiver, transmits the signals to the wearer's ear. The sound is released there and can once again be clearly perceived by the wearer.

To allow hearing aid wearers to enjoy problem-free hearing, hearing aids specifically amplify sounds that are important for communication and reduce disruptive sounds. This process is fully automatic in modern hearing aids.
2 men look at cellphone in noisy environment

Why hearing aids can do more than simply “make things louder”

Impaired hearing means more than simply hearing less well. It also means difficulties in understanding. Noises differ with respect to tone, with some being more shrill or some more buzzing. Certain sounds are typically perceived as unpleasant, or even painful. In such cases, „making things louder“ is not the right way to help people hear better again.

Determining the right volume

Technology for amplifying sound signals is vital. People with impaired hearing can only hear sounds above a certain volume, meaning these sounds must be louder than for those with good hearing. However, if everything were to be made louder, a noise such as a police siren would be absolutely unbearable. This is why hearing aid adjustment is used to determine the hearing aid wearer's discomfort threshold. This threshold represents the sound level beyond which sounds are perceived as unpleasant. For most people with normal hearing, this value is around 100 decibels (dB), although the values vary according to the individual.

Background noise and exact frequency ranges

In addition to general volume, a hearing aid must amplify the specific frequencies that the wearer can no longer hear very well. Digital hearing aids, which are now state-of-the-art technology, are able to compensate hearing loss in various frequency ranges in a precise and targeted way.

The real challenge – for both technology and humans – is to filter out background noise. During conversations in busy restaurants, for example, even people with normal hearing rely on some very complex processing mechanisms to single out a friend's voice. Modern hearing aid technologies feature special functions that significantly improve speech comprehension in such difficult situations.

In order to cope with difficult situations, modern devices also feature various hearing programs for different hearing contexts, such as restaurants or listening to music. Hearing aids also have several frequency channels, making it possible to adapt sound amplification individually to the wearer's needs. Background noise and unpleasant feedback whistling can also be suppressed.

Other technological aids

Many behind-the-ear models have a T-loop (telecoil) or induction loop. This is useful during telephone calls as it transfers the speech signals from the telephone directly to the ear. This significantly improves sound quality and speech comprehension. With a telecoil, induction systems, such as those installed in meeting rooms, theaters, or churches, can be used without any additional devices. This allows speech to be received directly via the hearing aid, while disruptive background noise is filtered out.

Hearing aids with Bluetooth are able to receive speech and music wirelessly from other Bluetooth-enabled audio sources (mobile phones or TV sets) over short distances. In some cases, a small, additional device (streamer) is required, which is positioned between the devices to transfer the signals.

Today, there are also apps that can be used to control the hearing aid via a smartphone. This means the hearing aid can be controlled wirelessly.

Alternatively, our expert audiologists are happy to show you the latest models and advise you on which is best suited to you.

If you are unsure whether or not you need a hearing aid, you might be interested in our free hearing test. If the test confirms that your hearing is impaired, we recommend you visit one of our clinics and speak with our audiology team.

The history of the hearing aid

Once used exclusively by royal eavesdroppers, hearing aid use has only become popular in the last 200 years. Few people are aware that the first hearing aid for which a patent was registered was worn by Queen Alexandra of England in 1901.
Higher-level everyday technology
This was just one of the many important steps in the hearing aid success story. For many people they have become an everyday item, such as glasses or smartphone apps. Life without these technical devices would be almost inconceivable. And just like smartphones, the latest generations of hearing aids are becoming smaller and increasingly powerful. The latest BTE and ITE hearing aids are able to improve hearing and provide natural sound thanks to their state-of-the-art technology and small size. Hearing aid development may appear to have been rapid, but in fact it goes right back to the 17th century.
The first hearing aids were unwieldy, but effective.
In the 17th century, a rather cumbersome device was used. Funnel-shaped hearing trumpets amplified sounds by 20 to 30 dB, significantly improving hearing and quality of life.
The development of the telephone
It was the invention of the telephone in the 19th century that paved the way for the development of the electric hearing aid. At the time, telephone technology was still bulky and unwieldy.
The first portable hearing aid
In 1901, American engineer Miller R. Hutchinson registered a patent for the first portable hearing aid. The device, which was owned by Queen Alexandra of England, was significantly smaller, but still weighed a stately 12 kilograms.
The first BTE hearing aid
By the 1940s, hearing aids had already shrunk to the size of a cigarette packet. The introduction of the transistor in the 1950s marked a breakthrough. The foundations for behind-the-ear hearing aids had been laid.
The beginnings of digital hearing aids
By the 1980s, BTE and (later on) in-the-ear hearing aids were already of a very high technological standard. Then the digital revolution reached the field of hearing aid technology. Hearing aids have undergone constant development right up to the present day, achieving the most natural and clear sounds possible. Devices are becoming ever smaller and more discreet, and are now scarcely visible in the ear.

In modern hearing aids, digital technology is allowing even those with severe hearing loss to fully experience life through all their senses.

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