Hearing aids are small but mighty pieces of technology. So how does a hearing aid work? There are several different elements to hearing aids, and how a hearing aid works depends on the type of aid it is. At its most basic, there are three main hearing aid parts—a microphone, an amplifier, and a speaker. The microphone receives sound and converts the sound to electrical signals. The electrical signals are passed to the amplifier, which increases the power of the signals and then sends them through the speaker to the ear. Keep reading to understand all the hearing aid parts for different models.
Behind-the-Ear Hearing Aid Parts
A behind-the-ear (BTE) style is what normally comes to mind when someone mentions “hearing aids.” Let’s look at BTE hearing aids first, and then discover how the other models differ from the BTEs.
In a BTE style, the microphone, amplifier, and speaker are situated in a hard case that sits behind the ear. This part of a BTE hearing aid must be kept clean and dry in order to keep the parts working properly. BTE hearing aids also consist of an earmold, or a plastic or acrylic dome that fits securely in the ear canal to provide a seal for the electronic sound the microphone is transmitting inside. There are several different shapes of earmolds and domes depending on the severity of the hearing loss. The earmold or dome is connected to the microphone and speaker via a plastic tube, which transmits the electronic sound into the ear mold. A BTE model also consists of a battery compartment, located in the hard case behind the ear.
In-the-Canal and Completely-in-Canal Hearing Aids
There are two types of hearing aid styles that fit partially or totally in the ear canal. Like the BTE models, they also consist of a hard case that contains similar hearing aid parts such as the amplifier and microphone, but this case sits in the ear canal and it much harder to see. There is no plastic tubing or separate earmold—these hearing aids are one complete unit totally inside the ear. ITE and CIC models offer cosmetic advantages, but they also use smaller batteries which do not last as long and are more susceptible to earwax clogging the pieces.
In-the-Ear and Receiver-in-Canal Hearing Aids
ITE hearing aids are made for adults with mild to moderate hearing loss and can be two different styles—one that totally fills the area of your outer ear (called a full shell), and the other that only fills the lower half of the outer ear (half shell). Like ITC and CIC models, the ITE model is just one component that contains all the technology.
Receiver-in-canal models are similar to BTE hearing aids—they both have a casing with hardware that sits behind the ear and connects into the ear. On a receiver-in-canal aid, however, the speaker is placed in the ear canal and is connected to the amplifier and microphone inside the case by a thin electrical wire rather than a plastic tube.