In today's world, we often take many things in our daily lives for granted, without taking the time to understand where they come from or what life was like before them. Electricity, for example, has revolutionized our world and enabled immense progress in our quality of life.
Hearing aids are among those objects that many people use daily. They allow hearing-impaired individuals to lead a relatively normal life by giving them access to sounds they would otherwise not be able to perceive.
However, the hearing aid has not always existed. Here is an overview of everything you need to know about hearing aids: who invented them, how they work, and what types exist today.
The history of the hearing aid
The hearing aid as we know it today is largely the result of innovations from the modern technological era. The ability to miniaturize technology even allows certain hearing aids, like the CLARIA Atom, to fit entirely inside the ear canal, making them almost invisible to others.
While small, receiver-style hearing aids are likely what you spontaneously associate with hearing aids, devices designed for the hearing-impaired have not always been compact or discreet. Here is an overview of the many generations of hearing assistance devices used throughout human history, and how they function.
Ear trumpets
One of the very first forms of hearing aid was particularly bulky and cumbersome. Called ear trumpets, these devices were essentially large cones that narrowed down to an opening the size of the ear canal.
The use of ear trumpets was likely inspired by the reflex of cupping one's hand behind the ear to hear better, except that these devices took the principle much further. It is estimated that ear trumpets have been used since the 17th century. To provide context, this is the century when the Pilgrims arrived in America aboard the Mayflower and when Isaac Newton published his work on gravity.
Ear trumpets work a bit like a satellite dish for your ears, focusing sound onto your eardrum. Useful in certain situations, they remained cumbersome and also amplified all the noises present in the environment.
For these reasons, they were not really practical for all-day use. They were only taken out when absolutely necessary.
Over the years, many variations of the ear trumpet emerged to improve their usage. Among the products based on the same principle are ear tubes and auricles. The latter offered a hands-free solution, albeit one with a rather amusing look.
The carbon microphone
The next step toward modern hearing aids did not arrive until well over a century after the first uses of the ear trumpet. Assisted hearing then evolved into devices exploiting the power of electricity to amplify sounds.
Carbon hearing aids were the first form of non-acoustic hearing aid. They worked using a carbon microphone. This device allowed for the conversion of sound waves into an electrical impulse, which then powered a speaker that reproduced the same sound.
These hearing aids were not the most practical: they had to be placed on a table for the person to hear. Much smaller than the ear trumpets they replaced, these devices were still very far from today's hearing aids.
Vacuum tube hearing aids
Only a few years later, the vacuum tube hearing aid appeared. Its name comes from the vacuum tubes used to amplify sound. These tubes marked the beginning of electronics as we know them. These advancements allowed for the reduction of the size of hearing assistance devices.
They were not yet as portable as they are today. The vacuum tubes themselves were quite bulky, and the batteries needed to power them were not very portable either.
Many vacuum tube hearing aids consisted of several parts: they did not form a single, integrated unit. Each element was connected to the others by wires. These elements were generally an earpiece, a battery pack, and the microphone/amplifier unit.
Transistor hearing aids
In the mid-1950s, transistor hearing aids began to appear. You can think of the transistor as a more compact and energy-efficient version of the vacuum tube. These electrical components consumed significantly less power.
This allowed for the use of smaller batteries, making these hearing aids more portable. Add to that the progress in battery technology, and hearing aids began to resemble what they are today.
Since the mid-to-late 50s, the basic architecture of these hearing aids has remained relatively identical. Notable improvements have been made along the way: better microphones, better speakers, smaller components, and clearer sound.
Who invented the hearing aid?
Now that you know the broad strokes of the history of hearing aids, you may be wondering who deserves the credit for the very first one. While it would be nice to have a simple answer, the truth is that the hearing aids you know today are the result of the work of countless innovators.
These brilliant minds invented the various components that make a hearing aid work. From the battery that provides electricity to the microphone capable of capturing sounds, hearing aids are truly the collective work of hundreds of people throughout history.
While the invention of the hearing aid owes much to many inventors throughout history, one of them stands out: Miller Reese Hutchison. He created the first electric hearing aid. His design paved the way for all those that followed.
Created in 1898, this device quickly inspired others to develop their own versions of the apparatus. This eventually led to the innovations we know today.
Modern hearing aids
Now that you realize the considerable progress made in hearing technology, you may be wondering how these tiny devices manage such impressive results in such a small format.
Here is how modern hearing aids work, and what the different types available are.
In-the-ear hearing aid
In-the-ear (ITE) hearing aids are among the most popular options today because they pack a lot of power into a tiny format. They fit entirely inside the ear canal, which makes them nearly invisible to others when worn.
With an in-the-ear hearing aid, the speaker, microphone, and amplifier are all housed in the ear canal. These devices eliminate the external part of the earpiece, which some find annoying.
Traditionally, in-the-ear hearing aids were far too expensive for the average person, but CLARIA is shaking up the industry by offering this technology at a surprisingly reasonable price. With the EV1, EV3, and Atom ranges, you will find the option that matches both your needs and your budget.
Behind-the-ear hearing aid
The classic modern hearing aid, the one most people know, is the behind-the-ear (BTE) model.
Rather than housing everything discreetly in the ear canal, the behind-the-ear design places the battery, amplifier, and microphone behind the pinna. The speaker still goes into the ear canal, but the majority of the device remains on the outside.
This format is still widely used, but at the current pace of technological progress, don't be surprised if it disappears entirely in favor of in-the-ear models in the years to come.
Bone conduction hearing aid
So far, the hearing aids discussed all use air as a means to carry louder sounds to your ear. However, this does not work for all types of hearing loss.
Some people have hearing loss that prevents their middle ear from functioning properly. In these cases, conventional hearing aids are significantly less effective.
Bone conduction hearing aids are essentially identical to conventional hearing aids. But instead of sending electrical signals from the amplifier and microphone to a speaker, they are directed to a component called an oscillator. An oscillator is an electrical component that vibrates when a current is applied to it.
The oscillator is either in contact with the bone behind the ear or attached directly to the bone surgically. The vibrations thus reach the inner ear and allow you to hear.
Past, present, and future of innovation
Hearing aids have truly changed the lives of the hearing-impaired. Whether you were born hearing-impaired or if your hearing loss developed over time, they allow you to lead a relatively normal life, rich in sound.
Today's hearing aids are nothing like those of the past. Constant progress in science and technology now offers hearing-impaired individuals a solution of remarkable effectiveness.
Sources
The Hearing Aid Museum | Hearing Aid Museum Gallery
Miller Reese Hutchison - Newspaper Clippings | Birmingham Public Library Digital Collections
Bone Conduction Hearing Aids | Duke Health
