Last updated on Sep 19, 2018
At their most basic, hearing aids work by taking audio from the environment, amplifying and clarifying it, and transmitting the sound in its improved form to the inner ear. However, the ways that hearing aids function for the hearing impaired are much more complex than just that. Read on for helpful information about how hearing aids work and how advanced digital versions can help you hear even better.
Most hearing aids have three basic parts: a microphone, an amplifier, and a speaker. While different types of aids may have various supplemental parts, these three elements are included in virtually all hearing aids on the market today.
The first part of a hearing aid is called the microphone. The microphone picks up sounds from the user’s environment and converts them to electrical signals before transporting them to the amplifier/processor. There are primarily two different types of microphones for hearing aids: directional and omnidirectional (also called “non-directional”). Directional microphones typically pick up noises that are directly in front of the wearer, while omnidirectional/non-directional microphones detect sound from all directions around the user.
The second primary part of a hearing aid is the amplifier/processor. The amplifier/processor takes the electrical signals that were sent to it by the microphone and increases and improves the sound and quality of the audio information. Filters built into the amplifier/processor constantly work to remove extraneous, irrelevant, and distracting sounds from the data, such as background noise, wind, and other audio feedback.
The speaker, sometimes referred to as the receiver, is the final component of the hearing aid. It takes the modified electrical input from the amplifier/processor and converts it back into audio waves that are understandable by the ear and the human brain. The speaker’s audio output directly faces the wearer’s inner ear, so that the sound effectively reaches the proper structures in the ear that are responsible for hearing.
Depending on the type of hearing aid, the speaker may be physically inside the ear (as with in-the-ear/ITE models), or it may be attached to a tube that feeds into the ear canal (as with behind-the-ear/BTE models).
While practically all modern hearing aids have the three primary elements described above, most also have additional parts. While these extra features will vary from model to model, some of them include: battery compartment, volume control, on/off switch, and a wax guard.
In the past few years, major advances in hearing aid technology have led to huge improvements in the quality and effectiveness of hearing aids. Nowadays, digital hearing aids actually include a small computer within the device itself, which performs a variety of highly advanced functions.
The computer’s settings can be adjusted to help improve hearing even more by filtering out background and extraneous noise, combating the symptoms of tinnitus, and much more. In fact, digital hearing aids can be programmed to an individual’s specific type or level of hearing loss, customizing the device to their unique needs.
Similarly, newer models of behind-the-air (BTE) hearing aids often include a piece of technology called a telecoil, which is essentially a small coiled wire inside the body of the aid. Whereas the microphone takes environmental noise and converts it into electrical signals, the telecoil functions by “hearing” magnetic fields that represent sound. This is especially helpful when a wearer is using a telephone or cell phone, as they can switch to “telecoil mode” and then only hear an enhanced version of the speaker on the line. Telecoil technology is also used in churches, auditoriums, theaters, and more to reduce feedback and distracting background noise, providing much clearer, louder audio.
Hearing aids are powerful devices that can help improve your hearing and, as a result, improve your overall quality of life. With constantly evolving and advancing technology, the ways that hearing aids work to help you hear are improving, as well. If you’re still undecided about whether or not you need hearing aids, check out this article on how hearing aids can improve your quality of life.