We might take it as a given that our hearing aids are hardly visible, can be controlled with our cell phones, and can distinguish between speech and background noise. What we might not realize, however, is that those capabilities are the products of 400 years of research, design, and enhancement.
Even 5 years ago, hearing aids could not generate the clarity of sound generated today. To see why, let’s track the history of hearing aids—starting today and travelling backwards—to observe how hearing aids would have treated your hearing loss in four different years: 2016, 1985, 1940, and 1650.
2016 – Modern Digital Hearing Aids
It’s 2016 and you’re searching to address your hearing loss. You open up a web browser, search for a community hearing care provider, fill out a brief form, and arrange an appointment.
At your hearing exam, your hearing is screened using advanced computer technology that precisely measures your hearing. Then, with the help of your hearing care expert, you select a hearing aid that suits your needs from a wide selection of models.
Then, your hearing specialist programs your new hearing aids to amplify only the sounds and frequencies you have difficulty hearing, leading to crystal clear sound without distortion.
If you told anyone 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 essence, digital technology.
For most of their history, there was no way for hearing aids to discern between assorted sound frequencies. Hearing aids would enhance all inbound sound, including background noise, producing distorted sound.
The digital revolution addressed that issue. With digital technology, all information can be transformed, saved, and manipulated as permutations of 0’s and 1’s. Digital technology made it possible for hearing aids to convert sound frequencies into digital information, which could then be characterized in accordance with which sounds should be amplified (speech) and which should be suppressed (background noise).
The first all-digital hearing aid was manufactured in 1995, and since that time the technology has improved tremendously, eventually to incorporate wireless capability.
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 internet because the first commercial internet service provider won’t be founded until 1989.
You’d need to use the phone book, depend on recommendations, or drive around the neighborhood to find a hearing care practice.
After scheduling a consultation and having your hearing evaluated, your options for hearing aids are very restricted. With no microprocessor and digital technology, hearing aids were built with a sequence of transistors. This adds size and higher power requirements, leading to larger batteries and larger hearing aids.
Additionally, without the benefit of digital technology, the hearing aid cannot distinguish between different frequencies of sound. Hearing aids receive incoming sound and the transistors act as simple amplifiers, amplifying all sound. So if you’re in a noisy room, speech recognition will be just about impossible.
1940 – Vacuum Tube Hearing Aids
It’s 1940 and you’re interested in acquiring a hearing aid. Transistors haven’t been applied to hearing aids yet, so your options are limited to vacuum tube hearing aids.
Vacuum tubes utilize more power than transistors, so the hearing aids require larger batteries, making the hearing aids big, heavy, and cumbersome.
And once again, without digital technology, the hearing aids can only act as straightforward amplification devices, 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. That means 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, much like what happens when you cup your hands around your ears.
By 1650, devices were developed that concentrated inbound sound into the ears, and these devices were called ear trumpets. They were prominent gadgets with a conical end that picked up sound and a narrow end that concentrated the sound into the ear.
This would be the only technology obtainable to those with hearing loss for the following 250 plus years.
Let’s return to 2016. Over more than 400 years of history, hearing aids have advanced 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 much better at distinguishing between various types of sound, and in amplifying only selected kinds of sound (like amplifying speech while suppressing background noise).
Each generation of hearing aid has produced a major upgrade over the previous generation. The question is, what’s the next great benchmark in the history of hearing aids?
Will we soon be able to improve natural human hearing, rather than simply restore it?