Understanding Hearing Aid Parts & Components
- Last Updated: Feb 25th, 2019
- Posted by: admin
- Category: Hearing Aids
Hearing aids are like mini computers fitted in your ear with a lot of technology packed inside it. You may not feel the need to know the working of the technology as long as you can hear, after turning it on, but it is better to have some basic understanding of various parts used in your hearing aid as they help bring sound back in your life. Visit an audiologist (1800-121-4408) today!
Hearing aids are a small machine that helps deaf people to hear louder and clearer. When people are facing trouble to hear, its help to improve your hearing by amplifying soft sounds. Therefore, Ear machine increases the sound vibration entering the ear. Ear machine for a deaf person works in many ways.
Common Hearing Aid Parts
Regardless of the type, some parts are common in all types of hearing aids. Following are the various parts of the hearing aid:
The microphone is the first step towards the hearing world. It picks up the sound and sends it to the amplifier/processor after converting them into an electrical signal which can be understood by a processor. Earlier the microphones were not able to differentiate between the speech and background noise. To enhance speech and conversation and minimizing input from background noise, the directional microphones needed to be adjusted. But now it is not so. Now the microphones process the sound differently to give a seamless hearing experience.
Microphones are of two types: directional and omnidirectional. Directional microphones are designed to pick up sound from the front of the wearer which will be helpful to understand conversation in a noisy environment. Whereas Omnidirectional microphones pick up sound from each and every direction and give the user a real-time experience. To create a more natural hearing experience, new hearing aids are equipped with both types of microphones to help wearers pick up sound from multiple directions.
It will be beneficial to keep this part of the hearing aid clean and dry. To do so, wipe the hearing aid with a soft and dry cloth before keeping them away at night. This is the most basic routine suggested by the manufacturers. This will help to keep the screen of microphone clean, free of debris and working properly. If we see BTE hearing aid, the microphone is located in the hard case to be fitted outside your ear.
The processor or amplifier is viewed as the computer or motherboard of your hearing aid. It will take the received electric signals from the microphone and convert it to a digital form that can later be manipulated. This is the step when the digital signal is adjusted according to wearers requirements. It also includes the need for sound amplification which will effectively accommodate the person’s hearing loss. This enhances the intensity of the signals.
As per the requirement, any type of feedback or noise from wind is canceled or reduced. This is where any masking feature for tinnitus can be added. As soon as the other appropriate adjustments are done to the digital signal, it is then converted back to an analog signal. After this, the signal is sent to the next hearing aid component.
Processor holds the bulk of a hearing aid technology. It can be programmed precisely by the hearing provider to meet your hearing profile. It can deliver a number of customized features. These can fit with a variety of hearing aid styles, regardless of the type of processor you use.
It will be the final component of the process and directed at the wearer’s inner ear. The receiver or loudspeaker will take the amplified signal or the enhanced sound wave from the processor and get it delivered to the ear canal where the final product can be heard. The signal sent from the processor must be converted into audible sounds before going to wearer’s ear. Due to the different styles of hearing aid, placement of receiver also varies based on this. If behind-the-ear style is considered, it styles like a receiver in the ear (RITE) and receiver-in-canal (RIC) sits closer to the eardrum.
Some hearing aids have their receivers placed directly in the ear canal like it is done in a completely-in-the-canal style.
This is the sole source to provide power to all the hearing aid component. Otherwise hearing aids will be of no use. These batteries come in four basic sizes which will be based on the type of hearing aid. They can be of two types: zinc-air disposables (most common) and rechargeable. The largest batteries are used to power BTE model, and they last for about two weeks. The smallest batteries are used to power In-the-ear models which lasts up to one week almost.
In most BTE models, the battery compartment is located near on/off switch on the casing that fits behind the ear. It is advised to remove batteries and keep this compartment open each night. This will allow evaporation of any accumulated moisture. The average lifespan of a hearing aid battery is from 5 to 14 days. Must check if the battery is inserted properly or not in case the hearing aid is not working. If it still doesn’t work after turning on, insert a new battery.
This may be the silliest part to explain but the most common reason behind the users thinking their devices aren’t working properly. If the BTE model is to be considered, the on/off switch is on the casing that fits behind the ear. Kindly check if the hearing aid is turned on or not, if it is not working. It is advised to switch off the hearing aid if not in use.
Some other hearing aid components:
BTE hearing aid hooks over the outside of your ear just like your eyeglass frames. This clear tube is also called an Elbow, which connects the microphone and amplifier casing to the tubing and earmold that fits inside the ear canal. This part will wear out easily and need replacement as perspiration and body oils break down the plastic. It should be wiped off thoroughly with a soft cloth or tissue to prolong its life. It’s really important to make sure the ear hook fits snugly, and not uncomfortably, on your ear. And also make sure that it’s connected securely to the casing and tubing.
It is a plastic tube which fits onto the end of the ear hook and transmits the electronic sound from microphone to earmold. Its length varies with the type of model and can be adjusted for better fit. These tubes are made of plastic and will need replacement even before your hearing aid wears out. Make sure to inspect these tubings daily to see if they are securely fastened to ear hook and earmold as well as for some signs of breakage of splitting.
Earmolds are of form-fitting plastic or acrylic components that fit snugly inside your ear canal and concha bowl (the outer ear closest to your ear canal). It provides an acoustic seal for the electronic sound, that microphone is piping inside. The shape and fit of the earmold depend on the model of hearing aid you choose and the severity of your hearing loss. There are many types of earmold, such as:
- Canal earmolds will fit only in the ear canal and will not extend to the concha bowl.
- Full-shell earmolds will extend into the concha bowl and are designed to give a natural appearance. This design is helpful to reduce feedback and works for moderate to severe hearing loss.
- Skeleton and semi-skeleton earmolds will be similar to full-shell earmolds. But they are aesthetically designed with a cutout portion.
- Half-shell earmolds will only cover the bottom half of the concha bowl. These are recommended for those who are suffering from mild hearing loss.
It is present in the hearing aid to allow the flow of air. It is also helpful in preventing the feeling of a plugged-up ear.
It provides access to all the users to make adjustments in the intensity of sound. This part may not be available for all types of hearing aid.
This is a small replaceable filter in a hearing aid. It is helpful in preventing earwax from getting into the internal components of hearing aid.
Custom-engineered case cover
This case cover is specially built cover. It is built to block out moisture, dust, wax, and oils.
HPF80 Nanoblock Coating
NanoBlock Coating is a protective layer which is used to safeguard all the sensitive circuitry from dampness and dirt. All the components are coated with this coating from inside and out.
The double layer of HPF 80 NanoBlock helps to keep the microphone free from any moisture and debris. This helps the sound to stay clear consistently.
Digital Signal Processor
It is advanced technology. It provides all the best features, to the hearing aid such as class sound quality, noise reduction, speech understanding, and comfort.
Gold-plated Battery Contacts
This is made up of real gold which is layered onto battery contacts. It helps to prevent corrosion, and therefore keep your hearing aids working like new.
This part of hearing aid is designed to be lightweight and shockproof. In this powerful receiver, Beltone legend features domes with a built-in wax guard.
This high-tech filter used in a hearing aid will trap moisture as well as particulate matter while allowing the sound to pass through it without any obstruction.
This antenna is of Beltone’s industry-leading 2.4 GHz wireless technology. This technology helps the wearer to hear clear sound from the TV, Stereo, PC or Phone.
How does a hearing aid work?
Hearing aids simply collect the sound near you, process it and release it back to the ear within no time. These are of types: analog and digital. An ear machine magnifies the vibration. And the hair cell detects the increased vibration and converts them into neural signals. These neural signals are then passed along the brain. The more the hair cell damage, the more the deafness or hearing loss. And the more ear machine amplification needed. In some cases, the inner ear damage is more than the larger vibration can convert. In those cases, an ear machine is not useful.
Steps of working procedures of the hearing aids
- Microphones pick up the sounds.
- The processing chip analyses sound.
- The amplifiers receive the processed sounds.
- The loudspeakers take the amplified sounds.
- Sounds are transmitted by the loudspeaker into the ear, via tubing in an earmold in the ear canal, or via a thin wire to the receiver in the ear.
- There is a transformation of the sounds in the inner ear into electrical impulses.
- The brain picks up the impulses and process it.
Therefore the hearing aid relies on the above working principle and finally you can hear properly and clearly.
Hearing aid parts according to the hearing aid style:
Behind-the-ear hearing aid parts
In BTE model, the microphone, amplifier, and speaker are fitted in a hard case that sits behind the ear. This part of the hearing aid must be kept clean and dry which will help to keep the parts in proper working condition. This model of hearing aid consists of an earmold that fits securely in the ear canal which provides a seal for the electronic sound the microphone will transmit inside. There are many shapes of earmolds and domes which depends on the severity of the hearing loss of the patient. The earmold or dome is connected to the microphone and speaker with the help of a plastic tube, that transmits the electronic sound into the ear mold. This model also consists of a battery compartment, located in the hard case which fits behind the ear.
In-the-canal and completely-in-the-canal hearing aid parts
There are mainly two types of hearing aids that fit partially or totally in the ear canal, like Behind-the-ear model. These models consist of a hard case containing similar hearing aid parts i.e. the amplifier and microphone, but this case sits in the ear canal and it is not visible properly. They don’t use any plastic tubing or separate ear mold. These hearing aids are one complete unit in themselves, which are totally inside the ear.
In-the-ear and receiver-in-canal hearing aid part
ITE hearing aids are specially designed for adults suffering from mild to moderate hearing loss. It can be of two different styles: one style that totally fills the area of the outer ear (i.e. a full shell), and the other style that fills only the lower half of the outer ear (i.e. half shell). In-the-ear model is just one component which contains all the technology. Receiver-in-canal models are very similar to Behind-The-Ear hearing aids model. Both of them have a casing with hardware which sits behind the ear and connects to the ear. In a receiver-in-canal hearing aid, however, the speaker is placed in the ear canal and it is connected to the amplifier and microphone inside the case by a thin electrical wire and not a plastic tube.
Need any help with Hearing Aids Devices? Call us 1800-121-4408 today, book an appointment for a FREE consultation for hearing aids at HearingSol Clinic.