Hearing Aids Explained

The Digital Revolution Has Arrived!
Today, hearing aids are smaller, more comfortable, and most importantly - more effective - than ever before, which explains why satisfaction with new hearing aids is at an all-time high of 90% (Kochkin, 2005). Hearing aids today are digital microcomputers that can automatically adjust to ensure sounds are audible and comfortable. And with a host of twenty-first century features, they're easy – and even fun – to use. Even basic models today are light years ahead of the most advanced models of just a few years ago.

That's great news, because in over 90% of cases of hearing loss, hearing aids are recommended. In fact, for most hearing loss, hearing aids are the only treatment. And research has proven that hearing aids not only help you hear better but can actually improve the quality of your life (National Council on Aging, 1999).

Kochkin, Sergei (2005). MarkeTrak VII: Hearing Loss Population Tops 31 Million. Hearing Review, 12 ,(7), 16-29.

Video: Hearing Aids Explained

Dr. Sandi Ybarra discusses the question "What is the best hearing aid on the market?" Your hearing experience is unique to you much like your fingerprint. Dr. Ybarra discusses the process for matching you with the correct hearing aid.

What is a hearing aid?
Hearing aids are miniature electronic devices that sit in or on the ear and selectively amplify and process sounds. All hearing aids contain one or more microphones to pick up sound, an amplifier that amplifies and processes sound, a receiver or speaker that sends the signal from the amplifier into your ear, and a battery or power source. All these components are packaged into various styles to fit people's cosmetic needs and power requirements.

Sound processing
Hearing aids today are digital, meaning incoming signals are converted into a series of numbers which is then processed using mathematical equations. Digital processing enables very complex manipulation of signals, for example, to separate speech from noise. Many hearing aids today have more processing power than your desktop computer – gone are the days when hearing aids were mere amplifiers. Complex algorithms separate sound into different frequency regions and amplify each region selectively, depending on the wearer's hearing loss. Algorithms also enable different amounts of amplification for soft, moderate, and loud sounds, so sounds are audible, but loud sounds are not uncomfortable or over-amplified. And, digital processing ensures a precise replication of the original signal with minimal distortion, resulting in excellent sound quality for even the most discriminating audiophiles.

Programmable adjustment 
Hearing aids today are programmable, meaning the amplification can be precisely fine tuned and the special features can be adjusted for each wearer, using special hearing aid software on a computer. Hearing aids are customized for both the hearing loss and the preferences of the person who wears them. 

Hearing aids are available in more styles and sizes than ever before, thanks to miniaturization of electronics and a new focus in the hearing industry on style and design. Now, more and more people can wear tiny, nearly invisible models, or sleek styles that are much less conspicuous than the latest Bluetooth headsets. 

In-the-Ear Styles

Hearing aids worn in the ear are usually custom-fit, based on a cast or impression of the ear. They're available in different skin tones to camouflage with the outer ear. There are several styles – each is listed below, ranging from smallest to largest. 

Invisible-in-the-Canal (IIC)

The smallest hearing aid style is the IIC. This fits deep in the ear completely out of view past the second bend of the ear canal providing an invisible fit. The cosmetic advantages of this hearing aid can appeal to a wide variety of people who do not prefer a more visible option. They fit mild to moderately severe hearing losses.

Completely-in-the-Canal (CIC)

The smallest custom style, CIC instruments fit deeply and entirely within the ear canal. They fit mild to moderate hearing losses and offer high cosmetic appeal as they're nearly invisible when worn.

In-the-Canal (ITC)

ITC instruments sit in the lower portion of the outer ear bowl, making them comfortable and easy to use. Because they're slightly larger than CIC models, they have a longer battery life, and can host additional features such as directional microphones for better understanding in noisy environments, and controls such as volume controls. They fit mild and moderate hearing losses. 

Half Shell (HS)

Half shell models fill half the bowl of the outer ear. Like ITC models, their size enables the addition of features such as directional microphones, volume controls and push buttons to activate special settings for different listening environments. Because of their size, they may be easier than smaller models to handle for some people and yet are still often disguised by hairstyles or sideburns. This hearing aid style looks similar to the ITC hearing aid when worn on the ear, but is slightly larger.

Full Shell or In-the-Ear (ITE)

Full shell models sit flush within the outer ear bowl. Their size allows the maximum number of additional controls and features such as directional microphones, which require space on the outer portion of the instrument. They use a larger battery size than the smaller styles, and can fit a larger receiver with enough power for even some severe hearing losses. Because of their flexibility, they're widely recommended for mild to severe hearing loss. 


Behind-the-Ear Styles

Behind-the-Ear (BTE) models sit behind or on top of the outer ear, with tubing that routes sounds down into the ear that connects to an ear tip or earmold to secure them in the ear canal. BTEs come in colors to blend with hair or skin tones, and even chrome colors, leopard print and other funky designs to suit personal styles. Different BTE sizes accommodate different features, controls, battery types and degrees of power (larger instruments generally have more power than smaller ones). While many people choose discreet BTEs that are unnoticeable when worn, others are tempted to show off the cool designs.


Mini BTE with slim tube and tip

Mini BTEs are designed to hide behind the outer ear, and have ultra-thin tubing to discreetly route sound into the ear. The tubing connects to a soft tip that sits in the ear canal but doesn't occlude it. The result is a natural, open feeling as airflow and sound enter the ear naturally around the tip, while amplified sound enters through the tip. This is known as "open fitting" and is recommended for mild to moderate high frequency losses.


Receiver in the ear (RITE)

RITE models, also known as RIC (receiver-in-canal) models, are mini BTEs that have the speaker of the instrument incorporated in the ear tip, instead of in the main body of the instrument. RITE instruments fit mild to severe hearing losses. This hearing aid style looks similar to the Mini BTE when worn on the ear. 


BTE with earmold

BTEs with earmolds fit mild through profound hearing losses. Their longer shape, following the contour behind the outer ear, generally can house more features, controls, and power than custom models. The earmold color and style, as well as the wearer's hairstyle, determine exactly how they'll look on each person.