How Do Hearing Aids Work

There are dozens of hearing aids to choose from, and if you’re not careful, you could invest in a product that’s not quite right for you, forcing you to spend more money on a replacement.

In this article, we break down how hearing aids work, the special features to look for and what questions to ask before your next purchase, ensuring that you have all the information possible to make the best choice for you.

Key Takeaways

  • There are two electronics within a hearing aid, digital and analog, and they both work in different ways.
  • Hearing aids have multiple parts and features, including multidirectional microphones and Bluetooth technology.
  • There are several hearing aid styles to choose from depending on your lifestyle, degree of hearing loss, and desired appearance.
  • Techniques such as wearing your hearing aid in different environments will help you adapt faster to your hearing device.

How Do Hearing Aids Work?

Hearing aids work like any basic amplifying sound system with three main parts:

  • Microphone – Picks up sounds and turns them into an electronic signal.
  • Amplifier – Strengthens the electronic signal and filters it through the device.
  • Speaker – Sends the amplified sound to your ear.

 Hearing Aid Parts

The hearing aid body encases the microphone, amplifier, and speaker, which we’ll go into detail about in the next section. But there are other electronic components, including:

  • Battery – The power source of the hearing aid.
  • Telecoil – A small copper wire coiled inside the hearing aid body that acts as a wireless receiver and directly connects you to assisted listening systems (ALS). T-coils reduce background noise and make it possible for you to hear better in public settings like airports, churches, theaters, and any other public locations with induction loop systems.
  • Programming Buttons/Setting Switches – Tiny buttons on the hearing aid body to switch between different hearing environments and volume functions. Some are pre-programmed by an audiologist or hearing care professional.
  • Transmitting Wire – A thin plastic wire that transmits signal and power to the speaker.
  • Domes – A small bell-shaped piece of plastic, rubber, or silicone connected to the end of the hearing aid’s receiver wire. They come in two different styles—open and closed style.
  • Earmolds – Plastic or silicon, custom-fitted for the individual wearer and designed to fit precisely in the ear canal.


The hearing aid microphone sends sound signals to the amplifier. They come in three different models—directional, omnidirectional, and adaptive.

Directional microphones pick up sounds from a specific direction in relation to the hearing aid position. This function is useful in getting rid of background noises. It allows the wearer to focus on sounds directly in front of them, perfect for conversations in noisy restaurants or social gatherings.

Omnidirectional microphones pick up sounds from the front, back, and side of the wearer. This type of microphone is better in quiet situations as it strengthens sounds equally from all directions.

Adaptive directional microphones are the latest hearing aid technology and automatically adjust to noise levels and sound environments.

This microphone picks up sounds from one direction but automatically changes direction based on voice sounds and speech signals, allowing the wearer to easily move in and out of different sound environments with minimal interruptions.


The amplifier, also called a processor, sends converted signals to the receiver or speaker and makes general sounds louder. An audiologist must program hearing aid amplifiers, but unlike the traditional sound amplifiers, they only pick up frequencies the wearer has a hard time hearing.


The speaker, also called the receiver, takes the electrical signals from the amplifier, converts the signal back into sound, and sends it directly to the ear. The speaker sits either in the dome or earmold, depending on the severity of your hearing loss or your desired look.

Digital vs. Analog Hearing Aids

The two types of electronics within hearing aids are digital and analog, and each functions differently. Analog converts soundwaves into electrical signals, whereas digital converts into numerical codes that contain information about the sound such as pitch, loudness, and frequency.

Digital Hearing Aids

Digital hearing aids work like powerful computers, adapting to your personalized needs, preferences, and type of hearing loss. More than just making things louder, individual sound signals create natural-sounding audio to help the user understand different noises.

You can customize your hearing experience to your specific hearing loss with frequency channels and hearing programs that prevent feedback whistling, reduce disruptive sound waves, and suppress background noise.

This type of hearing aid is the latest in digital technology, improving sound quality and speech comprehension, and connects to your smart device or Bluetooth technology.

Analog Hearing Aids

Analog hearing aids are not as common as they once were but are still a more affordable option for mild to moderate hearing loss.

Analog hearing aids are notably more affordable than digital options, which can easily reach $5,000 or more

Because analog devices lack the technology to adapt to different scenarios automatically, these hearing aids have only basic components. However, some are programmable and can contain multiple applications for various sound environments, for example, quiet home conversations, telephone calls, noisy restaurants, and theater experiences.

The amplification of these hearing aids continuously increases the sound waves creating a somewhat unnatural sound, but it’s something that most wearers adapt to reasonably quickly.

Types of Hearing Aids

There are a few different types of hearing aids to choose from, varying in size, special characteristics, and how they fit within your ear. Your personal preference and your hearing needs will determine which style is right for you.

Behind the Ear Hearing Aids

Key features: 

  • Speaker built into an insertable ear dome.
  • All parts fit into the tiny case behind the ear.
  • Rechargeable battery option.
  • Telecoil option available.


  • Made by all major hearing aid companies.
  • Speaker can be replaced separately.
  • Above-average sound quality.
  • Made for those with severe hearing loss.


  • Speaker susceptible to moisture and ear wax damage.
  • The microphone and processor sits behind the outer ear and is visible.

A behind-the-ear (BTE) hearing aid is probably the hearing aid you’re most familiar with. This style has a tube that loops over the ear and sits on top or directly behind the outer ear. The other end of the tube joins the hearing aid to a custom earmold or dome that fits tightly in the ear.

This style is the best hearing aid for adults and children with mild to severe hearing loss.

Behind the ear, BTE hearing aids can be fitted with multiple components such as directional microphones, wind noise reduction, and rechargeable batteries. Some of the newer mini designs are less visible and more effective.

In the Ear Hearing Aids

Key features:

  • A larger case able to house more components.
  • Worn entirely inside the ear.
  • Remote control technology available with some units.
  • Can connect to wireless devices.


  • Easier to handle for those with dexterity issues.
  • More discreet than other styles.
  • Perfect for glasses wearers.
  • Uses a larger battery for longer battery life. 
  • Easy to insert.


  • Can create a plugged-up feeling.
  • May pick up more wind noise because of the larger size.

In-the-ear (ITE) hearing aids, or in-the-canal (ITC), fit either in the bowl-shaped area of the outer ear or, more commonly, in the lower ear canal. This type of hearing aid is best for people with mild to moderate hearing loss, but more advanced accessories are available for anyone with more severe hearing loss.

These devices are easy to handle, come in various sizes, and are more comfortable for people with active lifestyles.

ITE hearing aids are more susceptible to ear wax build-up, clogging, and moisture damage, so it’s important to follow instructions on caring for your device.

Receiver in Canal Hearing Aids

Key features:

  • Directional microphones.
  • Manual control options.
  • Speaker built into the insertable ear dome.
  • Rechargeable battery option.


  • Above-average sound quality.
  • Speaker can be replaced separately.
  • Can connect to wireless devices.


  • Susceptible to ear wax clogging and moisture damage.
  • Can be uncomfortable and hard to use.

The receiver-in-canal (RIC) device, also known as receiver-in-the-ear (RITE) and canal receiver technology (CRT), is popular for new hearing aid users and best for those with mild to moderate hearing loss.

This style is similar to a behind-the-ear hearing aid, but instead of tubing, only a thin wire connects the microphone and processor behind the ear to the speaker, which sits in the ear canal.

Having the speaker in the ear canal reduces the plugged-up feeling you might find in other devices and offers a more natural flow of sound.

Completely in the Canal Hearing Aids

Key features:

  • Ear canal impression used to create a custom fit.
  • Comes in a variety of skin tones and colors.
  • Can sync to smart a device.


  • Smallest and least visible hearing aid.
  • Custom-fit for excellent sound quality.
  • Less sensitive to wind noise.
  • Less feedback from telephone and other interference.


  • No extra features such as volume control or directional microphone.
  • Not for those with profound hearing loss.

As the name suggests, completely-in-the-canal (CIC) devices fit entirely inside your ear canal for almost invisible wear. These are ideal hearing aids for adults with mild to moderate hearing loss.

Because this device fits deep within the ear canal, removal occurs by tugging on a small string attached to the device. The batteries used for these completely-in-the-canal hearing aids are quite small and do not have a long lifespan.

In general, completely-in-the-canal (CIC) hearing aids can be difficult to handle and adjust. Still, the nearly invisible style makes it popular for those concerned about the cosmetic effects of wearing a hearing aid.

Open Fit Hearing Aids

Key features:

  • An improved version of BTE hearing aids design.
  • Ear canal is almost completely open.
  • Digital feedback suppression technology.


  • Does not cause a plugin effect.
  • A better, more natural voice sound.
  • Little to no telephone feedback.


  • More visible than other models.
  • The non-custom dome makes it more difficult to insert.

An open-fit hearing aid is set up like behind the ear (BTE) hearing aids but uses a thin tube similar to RIC or RITE hearing aids only with an open dome in the ear. Keeping the ear canal open allows low-frequency sounds to enter the ear naturally while high-frequency sounds are amplified through the hearing aid.

This hearing aid is better for those with mild to moderate hearing loss or anyone suffering from excessive earwax build-up.

The open-fit hearing aid is small, can be challenging to use, and requires a good amount of dexterity to operate, but the size makes the device less susceptible to earwax build-up and blockages.

How to Start Using a Hearing Aid

Your audiologist or hearing aid specialist will program your device and give you instructions on using your hearing aid—what the special features are and how to use them. Be aware that it will take some time to get used to your new device, even if you’ve had one before, so be patient with yourself.

Get Familiar With All the Features

Additional hearing aid components can enhance your device and improve the quality of your experience:

  • Directional Microphones – Picks up and improves sounds from behind and beside you.
  • Noise Reduction – Eliminates background environmental noises, so isolated voices sound louder. Some devices offer wind noise reduction making it easier to hear.
  • Rechargeable Batteries – Some hearing aids offer rechargeable batteries, eliminating the time and cost of regularly replacing disposable batteries.
  • Wireless Connectivity – Hearing aids with wireless connectivity can connect with Bluetooth-enabled devices such as cell phones, tablets, and television.
  • Remote Controls – More advanced hearing aids come with remote control technology to control the device settings and can operate on a cell phone or tablet.
  • Variable Programming – This allows the wearer to store several pre-programmed settings in different environments within the hearing aids.
  • Direct Audio Input – This feature allows you to directly plug your hearing aid into audio from a computer, television, or music device with a simple cord.
  • Synchronization – This allows people with two hearing aids to program the devices to work together so that adjustments to program settings in one ear automatically change the other ear.

Charge It or Put Batteries In

Rechargeable or disposable, that is the question. Let’s look closer at how the two types differ and why you might want to choose one over the other.

Rechargeable Batteries

Rechargeable batteries are currently only available for behind-the-ear models and some in-the-canal (ITC) hearing aid models and come with a docking system. Some brands have rechargeable carrying cases for people on the go.

Check out affordable MDHearingAids for more information on these types of rechargeable brands.

Powering-up BTE hearing aids can happen at night or anytime the device is not in use. Some models only need a few hours to recharge, where others take a bit longer.

Disposable Batteries

Most hearing aid batteries are zinc-air button disposable batteries and are air-activated, meaning that the battery is inactive and will not lose life until the factory-sealed sticker is removed.

Zinc-air batteries are available in most retail stores, pharmacies, grocery, and electronic stores and can be stored for up to three years, allowing the user to buy batteries in bulk if necessary.

There are five sizes of disposable batteries, which are all color coded, making them easier for purchasing. The life span of these batteries is anywhere between five – 14 days, depending on the size and the amount of time the hearing aid is in use.

To Adjust or Not to Adjust?

Some hearing aid styles come pre-adjusted by an audiologist or hearing care professional, whereas others such as online and OTC brands are adjusted manually by the wearer.

If you’re interested in a pre-adjusted device for your type of hearing loss, you’ll need to complete a hearing test with an audiologist, or you can find the best online hearing tests here.

Once your new hearing aid is ordered, the audiologist will use that test to make the necessary adjustments to your device with your specific hearing needs in mind.

Pre-adjusted hearing aids are best for anyone with dexterity issues or difficulty operating smaller devices. However, the more technologically advanced hearing aid styles can be adjusted manually through a smart device such as a cell phone or tablet.

Reprogramming Hearing Aids

Over time, your hearing will fluctuate, and your device will not work as well as it once did. It’s advised to have regular check-ups with an audiologist, at least twice a year, to determine if your device requires re-programming.

Age has a significant impact on hearing, where roughly 43.2% of adults aged 70 and up suffer from hearing impairment

Signs that your device needs reprogramming:

  • Discomfort or pain around the ear.
  • Volume fluctuations.
  • Whistling noises in the ear.
  • Additional hearing loss.

Getting Used to Hearing Aids

The process of getting used to your device takes time and patience. You’ll become hyper-aware of your hearing, and everything, including your voice, will sound different.

Some things to keep in mind when you first start to wear hearing aids:

  • Start in a quiet place. Make sure you know what your device sounds like without external noises first. This will make it easier to make adjustments later.
  • Gradually increase wear over time. You don’t want to become overwhelmed, so start with only a few hours of wearing your hearing aid. The more you use it, the more you’ll get used to the new sounds.
  • Practice wearing your hearing aid in different environments. Hearing aids may react differently depending on the environment you’re in, especially if you have a device with dual microphones.
  • Wear hearing aids regularly. The more you wear your hearing aid, the more you’ll get used to it. But keep in mind that hearing aids do not restore normal hearing.
  • Follow up with a hearing care professional. Adjustments or re-programming might be necessary, and an audiologist will suggest any changes if needed. Good maintenance is key to keeping your products functioning correctly. Learn more about how to clean hearing aids here.

Over the Counter Hearing Aids vs. Professional Hearing Aids

Over-the-counter (OTC) products come pre-programmed and are useful for people with mild to moderate hearing loss. Because they are not considered medical devices by the food and drug administration, they are sometimes called personal sound amplification products (PSAP).

Most of these devices don’t have special features and only amplify general noises. Other differences between OTC brand hearing aids and professional styles are:

  • OTC hearing aid devices are cheaper than their prescription and professional counterparts.
  • They come pre-programmed and do not require assistance from a hearing professional.
  • The sound amplification can be minimal.
  • Most OTC products are one size fits all.
  • Only behind the ear and in the ear models are available.
  • There are no additional aspects like program amplification or rechargeable batteries.
  • The warranties and guarantees will be considerably less than professional hearing aids.

Hearing Aid FAQ

Do Hearing Aids Work for Everyone?

There’s such a variety of hearing aid styles and features, making it easy to find a hearing aid that works for you. If you have a problem choosing a device, or the one you currently have is not working, visit an audiologist for testing and recommendations.

How Bad Does Hearing Have to Be for Hearing Aids?

Anyone who desires to boost their hearing in various environments can benefit from hearing aids. Visiting an audiologist or even an ear nose and throat professional can help determine the reason for your hearing loss.

Anyone of any age can use a hearing aid or any assistive technology to boost their hearing

How Do Hearing Aids Help Tinnitus?

Hearing aids can mask the sound of tinnitus by increasing the external sounds and drown out the tinnitus noise a person might hear, allowing them to concentrate on outside noises.

This also increases stimulation to the brain, improving communication for those who have lost the ability to hear due to tinnitus. You can find more information on tinnitus by visiting the National Institute on Deafness and Other Communication Disorders.

How Do Hearing Aids Sound?

Hearing aids do not sound like natural hearing, but most users quickly adapt to the new sounds. If you experience feedback such as whistling, squeaking, static, or wind noise, visit your audiologist for a possible re-programming of your device.

Are Over the Counter Hearing Aids Any Good?

There are many reputable OTC hearing aid styles in the market with positive reviews and satisfied customers. Unless you’re experiencing severe hearing loss, OTC hearing aids may be a better option, especially if you’re looking for immediate and less expensive purchases.


There are several hearing aid models, styles, and types to choose from, and once you start looking into the individual features, you’ll find that there’s something out there for almost everyone, no matter your degree of hearing loss.

It’s possible to find the perfect hearing aid of your choice online or at your local pharmacy. For a more personalized experience or advanced model, visit your local audiologist for information on the latest hearing aid technology available.