If you’ve found this post, the chances are that you would like to know: how do hearing aids work?
There will come a time for everyone, normally in older age, when it starts getting difficult to hear. At that point, you can either choose to carry on cupping your hand to your ear and asking everyone to repeat themselves, or getting a hearing aid!
There’s a conception that hearing aids are complicated little bits of kit. So they can’t just be as simple as a little microphone and amplifier… Can they? Read on to find out more.
How do hearing aids work: What’s inside a hearing aid?
Every single hearing aid has the same basic mechanical function. They pick up the sounds around you and amplify them so that you can hear them more easily. Because most hearing aids are manufactured in the same sort of way, they also have the same key components, which are:
- A tiny microphone. This part sits on the outside of the hearing aid, and picks up sound as it hits your ear. The microphone, like all microphones, then converts this sound from the analog vibration of a small drum or diaphragm (just like your eardrum, as it happens) into digital signals.
- A microchip, which controls the operation of the hearing aid. This microchip can determine whether a sound is loud or quiet, and therefore whether it actually needs to be amplified. It can also determine between noises like traffic, which you wouldn’t want to be any louder, and speech, which you would.
- Third, and probably the most important part of the hearing aid, is the amplifier. The amp increases the strength of the digital signal being received from the microphone.
- The receiver converts the digital signal back into an analog vibration, which passes through your ear canal and hits your eardrum, just as normal sound would. The only difference is that the amplifier strengthened that digital signal, which effectively made the sound louder, and therefore easier for you to hear.
- Last but not least, all hearing aids need a battery. Without the battery, none of the other components would be able to do their job! Most hearing aids these days don’t need the larger sized batteries that older hearing aids did, which means they can be more compact.
How do hearing aids work: What different kinds of hearing aids can I buy,?
There are three main kinds of hearing aids available on the market today. You might prefer one kind over another, or you might not mind. But the choice is yours.
- Behind-the-ear hearing aids are the old fashioned kind you may be used to seeing. They consist of a hard plastic case worn, as the name suggests, around the ear. The components sit in the small case behind the ear, whereas the receiver sits inside the ear. They work just as described above, and can be used by people with mild to severe hearing loss.
- In-the-ear hearing aids sit entirely within the outer ear. That is, they’re held in place entirely by plugging up the ear, rather than the small hook that BTE hearing aids have. ITE hearing aids are much smaller, and the components therefore have to be smaller still. That’s why ITE and ITC hearing aids (more on those later) were only made possible by more recent innovations. ITE hearing aids aren’t suitable for children, because as they grow, they would have to have their hearing aid replaced too often. ITE hearing aids may also have a telecoil, which helps you to hear induction loop systems, found in many public spaces and facilities.
- In-the-canal hearing aids are even smaller than ITEs, and sit entirely within the ear canal. That means that they’re hardly even visible, so they’re suitable for you if you would rather people not know you need a hearing aid.
Which kind of hearing aid is right for me?
The question of which hearing aid is right for you is not straightforward to answer. First, comfort is an obvious factor. Behind the ear hearing aids are more comfortable within the inner ear, but are more cumbersome. Hearing aids which only fit in the inner ear, or in the ear canal itself, are easier to wear but can cause pain over time. The best way of identifying which is best for you is to try them out one by one.
Your level, and your kind of hearing loss is also an important factor. Behind the ear and in the ear hearing aids are best for more severe hearing loss, whereas in-the-canal hearing aids are better for mild hearing loss. Price, ease of repair, style and features are also ways of determining between a number of choices. Ultimately, the choice is yours, and your audiologist can advise you on which they think is best for you.
How do hearing aids work: Do all hearing aids work in the same way?
Really, the question ‘how do hearing aids work?’ is a little misleading. Because not all hearing aids actually work in the same way! There are analog hearing aids, and there are digital hearing aids. They work in subtly different ways. But the end result- better hearing- is the same.
Analog hearing aids work in the exact same way we’ve described above. They convert sound waves into digital signals, amplify those signals, and convert them back into sound. That sound is louder than you would have been able to hear otherwise. This is the way that hearing aids have worked for decades!
Digital hearing aids, on the other hand, convert sound waves into code- computer code, basically. Because the sound is converted into code, the microchip inside the hearing aid can analyse it and understand it. It can be programmed to amplify certain kinds of noise or certain frequencies. This allows the hearing aid to help you, and your individual needs, better: for instance if you only have trouble hearing sounds of a lower pitch, your hearing aid can be adjusted for that.