We may take it as a given that our hearing aids are barely noticeable, can be controlled with our smart phones, and can discern between speech and background noise. What we might not realize, however, is that those functions are the products of 400 years of experimentation, design, and development.
Even as early as 5 years ago, hearing aids could not generate the clarity of sound produced today. To see why, let’s track the history of hearing aids—beginning today and moving backwards—to see how hearing aids would have handled your hearing loss in four different years: 2016, 1985, 1940, and 1650.
2016 – Modern Digital Hearing Aids
It’s 2016 and you’re looking to treat your hearing loss. You launch an internet browser, search for a nearby hearing care professional, fill out a quick form, and arrange a consultation.
At your hearing assessment, your hearing is analyzed using sophisticated computer technology that precisely evaluates your hearing. Then, with the assistance of your hearing care practitioner, you decide on a hearing aid that meets your needs from a wide selection of models.
Then, your hearing specialist programs your new hearing aids to enhance only the sounds and frequencies you have difficulty hearing, producing crystal clear sound without distortion.
If you were to tell someone in the 1980’s that this would be the process, they wouldn’t have thought it was possible.
So what did render it possible? In a nutshell, digital technology.
For the majority of their history, there was no way for hearing aids to distinguish between assorted sound frequencies. Hearing aids would intensify all incoming sound, including background noise, generating distorted sound.
The digital revolution cleared up that problem. With digital technology, all information can be transformed, saved, and manipulated as permutations of 0’s and 1’s. Digital technology allowed hearing aids to convert sound frequencies into digital information, which could then be labeled according to which sounds should be amplified (speech) and which should be restrained (background noise).
The first all-digital hearing aid was created in 1995, and since that time the technology has improved significantly, eventually to include wireless functionality.
1985 – Transistor Hearing Aids
Now, imagine it’s 1985 and you’re looking to treat your hearing loss. You can forget about browsing for a local hearing care provider on the internet because the first commercial internet service provider won’t be established until 1989.
You’d need to use the yellow pages, depend on referrals, or drive around the neighborhood to find a hearing care practice.
After booking a consultation and having your hearing tested, your options for hearing aids are very limited. With no microprocessor and digital technology, hearing aids were engineered with a collection of transistors. This adds size and increased power requirements, resulting in larger batteries and larger hearing aids.
Additionally, without the advantage of digital technology, the hearing aid cannot differentiate between various frequencies of sound. Hearing aids receive inbound sound and the transistors function as simple amplifiers, amplifying all sound. So if you’re in a noisy area, speech recognition will be nearly impossible.
1940 – Vacuum Tube Hearing Aids
It’s 1940 and you’re contemplating purchasing a hearing aid. Transistors haven’t been applied to hearing aids yet, so your choices are restricted to vacuum tube hearing aids.
Vacuum tubes utilize more power than transistors, so the hearing aids demand larger batteries, making the hearing aids large, heavy, and cumbersome.
And once again, without digital technology, the hearing aids can only act as simple amplification devices, making all incoming sound louder. The hearing aids can’t enrich speech and cannot remove background noise.
1650 – Ear Trumpets
Let’s go all the way back to 1650. There’s no digital technology, no transistors, and no vacuum tubes. As a result, there is no way to transform sound into electrical currents that can be amplified.
With electrical amplification unattainable, your only possibility is mechanical amplification by focusing and compressing sound into the ear, similar to what happens when you cup your hands around your ears.
By 1650, products were developed that focused inbound sound into the ears, and these devices were called ear trumpets. They were large gadgets with a conical end that collected sound and a narrow end that concentrated the sound into the ear.
This would be the only technology accessible to individuals with hearing loss for the next 250 plus years.
Let’s return to 2016. Throughout more than 400 years of history, hearing aids have evolved from mechanical amplification devices to electrical amplification devices, from vacuum-tube-based to digital-based. They’ve become considerably more compact, lighter, and more effective and affordable.
They’ve also become better at differentiating among various types of sound, and in amplifying only certain types of sound (such as amplifying speech while suppressing background noise).
Every generation of hearing aid has generated a significant upgrade over the previous generation. The question is, what’s the next great benchmark in the history of hearing aids?
Will we eventually be able to enhance natural human hearing, rather than simply restore it?