How do Hearing Aids Work?

Hearing loss is on the rise in Australia. Presently, one in six Australians are affected by hearing loss, and this number is predicted to increase to one in four by the year 2050. Although there are a range of factors for this steep incline of people living with a hearing issue, the main reasons are ageing and repeated exposure to loud sounds. Modern day living is noisy, add that to the fact that young people are subjecting their ears to excessively loud music and it is not a surprise that hearing loss is becoming more prevalent.

It is hard to appreciate just how vital our hearing is as it is so well integrated into our daily life. We rely on it to work, to socialise, to communicate, and even to relax and unwind. It can alert us to potentially dangerous situations and help us to make the decisions to keep ourselves safe. So, when it starts to deteriorate, it can be confusing, lonely and even a little bit scary.

Left untreated, hearing loss can lead to isolation and feelings of depression as it can cut you off from people if they are unable to easily communicate with you. Although a hearing aid can never wholly restore your hearing, it can usually restore your ability to communicate, which will improve the quality of life for you and those around you.

Thankfully, hearing aids have come a long way in the last few years. Modern devices are significantly smaller and more efficient than their older counterparts. The idea behind them, amplification, however, is still considered the most effective way to treat most forms of hearing loss. Choosing the right hearing aid is something that should be discussed with a professional audiologist. Click here to book a free hearing test now.

Hearing aids can differ by:

	Design – Size, Style – some are available in different hair and skin tones or bright colours. Even the position the aid is worn in the ear can differ.
	The technology used – Is Analog or Digital technology used to achieve amplification? Is it suitable for all degrees of hearing loss or just one specific type?
	Special features – Some aids have extra benefits like Bluetooth compatibility, wind noise reduction, feedback management, and directional microphones.

Analog: The Simple Version

In their most simple form, hearing aids have four essential components. No matter what style or size, they all have a microphone, amplifier, loudspeaker (AKA receiver), and power supply.

1. The microphone receives the sound and converts it into an electric signal.
2. The amplifier, which is located between the microphone and loudspeaker, strengthens or boosts the electric signal which increases the amplitude of the sounds supplied by the microphone.
3. The loudspeaker then converts the electric signal back into sound which flows through the tube, ear mould and into the person’s ear.
4. The power supply or batteries make the whole thing possible.

So, essentially analog hearing aids convert all sounds received into electric signals, boost those signals, and turn them into louder sounds. They tend to amplify everything by the same amount. So if someone is speaking to you, their voice and all the background noise around you will be amplified. An analog hearing aid can be configured, to a certain degree, to boost the frequencies that you struggle to hear more than the ones you can already hear. Your audiologist will consult your audiogram to find out the exact pattern of frequencies you can and can’t hear and adjust the aid accordingly.

Programmable Analog Hearing Aids

The next step up from analog is programmable analog; these aids have a variety of settings that you can choose from to give you different levels of amplification in all kinds of everyday environments. When this hearing aid is manufactured the settings will be preset, again according to the exact pattern of frequencies you can and can’t hear, and you can flick between these settings using a small switch on the device when needed.

While these are more sophisticated than the standard analog aids, they will still amplify all sounds, including background noise.

Digital: A Little More Complex

These aids have a computer chip that intelligently analyses the sounds that are received by the microphone. They can convert the sound wave into digital signals rather than electric signals, and this allows the aid to process the sounds more complexly, figuring out which sounds you want to be amplified and which ones you don’t. It does this by using Digital Signal Processing (DSP)

DSP can make a difference in many things, including:

1. Improved Speech Understanding – Digital aids can intelligently amplify speech with the use of directional microphones. These are designed to pick up speech more when the source is in front of the user while ignoring sounds coming from the sides and back of the user i.e. background noise.
2. Gain adjustment – Gain is how much an amplifier increases a particular frequency. Digital hearing aids can automatically adjust the gain for around a dozen frequencies according to the wearers particular hearing loss.
3. Sound classification – This figures out whether the sounds being picked up are music, speech, traffic etc. and amplifies or reduces them selectively. So it knows what kind of environment you’re in and applies a specific amplification based on that knowledge. These aids can switch automatically between settings to match a person’s hearing loss with the environment they are in, so if someone has trouble hearing higher frequencies like children’s or women’s voices, the aid will automatically adjust to boost these frequencies. Analog aids can also do this to a lesser extent, usually by the wearer switching settings.
4. Less Feedback – Feedback managers are now a staple in digital hearing aids to reduce that high-pitched whistling sound significantly.

So basically, digital aids are not superior to analog aids because they amplify sounds better, it is more about how the sounds received can be processed in a much more intelligent way. The digital information that is produced by the digital aid directs the aid; this allows it to make speech clearer, or music more pleasant to listen to or to reduce traffic noise, all during the amplification process.

The ever advancing technology in hearing aids enables you to stay connected to the world around you. The first step is meeting with an audiologist who can assist you by testing your level of hearing loss and giving a diagnosis. Click here to book a free hearing test now.