We might take it for granted that our hearing aids are hardly detectable, can be managed with our smart phones, and can differentiate between speech and background sound. What we may not recognize, however, is that those functions are the results of 400 years of experimentation, design, and refinement.
Even as early as 5 years ago, hearing aids could not provide the clarity of sound produced today. To see why, let’s track the history of hearing aids—starting today and moving in reverse—to observe 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 address your hearing loss. You open up an internet browser, search for a nearby hearing care professional, submit a quick form, and arrange an appointment.
At your hearing exam, your hearing is evaluated using state-of-the-art computer technology that accurately evaluates your hearing. Then, with the assistance of your hearing expert, you decide on a hearing aid that matches your needs from an extensive range of models.
Then, your hearing practitioner programs your new hearing aids to amplify only the sounds and frequencies you have trouble hearing, bringing about 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 make it possible? In essence, digital technology.
For most of their history, there was no way for hearing aids to distinguish between different sound frequencies. Hearing aids would magnify all inbound sound, including background noise, producing distorted sound.
The digital revolution resolved that issue. With digital technology, all information can be altered, saved, and manipulated as combinations of 0’s and 1’s. Digital technology enabled 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 suppressed (background noise).
The first all-digital hearing aid was created in 1995, and since then the technology has improved exponentially, eventually to incorporate wireless functionality.
1985 – Transistor Hearing Aids
Now it’s 1985 and you’re planning to treat your hearing loss. You can forget searching for a local hearing care provider on the web because the first commercial internet service provider won’t be established until 1989.
You would have to use the yellow pages, rely on recommendations, or drive around the neighborhood to find a hearing care practice.
After reserving an appointment and having your hearing screened, your choices for hearing aids are very limited. Without the microprocessor and digital technology, hearing aids were built with a collection of transistors. This adds size and increased power requirements, resulting in larger batteries and massive hearing aids.
Additionally, without the benefit of digital technology, the hearing aid can’t distinguish between various frequencies of sound. Hearing aids receive incoming sound and the transistors function as simple amplifiers, amplifying all sound. So if you’re in a loud area, speech recognition will be virtually 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 options are confined to vacuum tube hearing aids.
Vacuum tubes utilize more power than transistors, so the hearing aids call for larger batteries, making the hearing aids large, heavy, and cumbersome.
And once again, without digital technology, the hearing aids can only act as straightforward amplification systems, making all inbound sound louder. The hearing aids cannot enhance speech and can’t remove background noise.
1650 – Ear Trumpets
Let’s travel 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 option is mechanical amplification by concentrating and compressing sound into the ear, similar to what takes place when you cup your hands around your ears.
By 1650, devices were developed that concentrated inbound sound into the ears, and these contraptions were labeled ear trumpets. They were prominent devices with a conical end that picked up sound and a narrow end that focused the sound into the ear.
This would be the only technology accessible to those with hearing loss for the following 250 plus years.
Let’s return to 2016. Over the course of more than 400 years of history, hearing aids have improved from mechanical amplification devices to electrical amplification devices, from vacuum-tube-based to digital-based. They’ve become significantly more compact, lighter, and more efficient and affordable.
They’ve also become better at differentiating among different types of sound, and in amplifying only specific types of sound (like amplifying speech while suppressing background noise).
Every generation of hearing aid has made a significant upgrade over the previous generation. The question is, what’s the next major milestone in the history of hearing aids?
Will we eventually be able to improve natural human hearing, rather than merely restore it?