We might take it for granted that our hearing aids are scarcely detectable, can be operated with our smartphones, and can distinguish between speech and background sound. What we might not recognize, however, is that those features are the results of 400 years of experiment, design, and improvement.
Even 5 years ago, hearing aids could not deliver the clarity of sound generated today. To see why, let’s track the history of hearing aids—beginning today and going backwards—to see how hearing aids would have treated your hearing loss in four different years: 2016, 1985, 1940, and 1650.
2016 – Modern Day Digital Hearing Aids
It’s 2016 and you’re searching to treat your hearing loss. You launch an internet browser, search for a local hearing care provider, submit a brief form, and book an appointment.
At your hearing exam, your hearing is tested using sophisticated computer technology that accurately assesses your hearing. Then, with the assistance of your hearing consultant, you decide on a hearing aid that meets your requirements from a vast selection of models.
Then, your hearing professional programs your new hearing aids to magnify only the sounds and frequencies you have trouble hearing, giving you crystal clear sound without distortion.
If you told anyone in the 1980’s that this would be the process, they wouldn’t have believed it was possible.
So what did render it possible? In essence, digital technology.
For the majority of their history, there was no way for hearing aids to distinguish between different sound frequencies. Hearing aids would intensify all incoming sound, including background noise, creating distorted sound.
The digital revolution addressed that issue. With digital technology, all information can be altered, saved, and manipulated as permutations of 0’s and 1’s. Digital technology allowed hearing aids to transform sound frequencies into digital information, which could then be identified according to which sounds should be amplified (speech) and which should be restrained (background noise).
The first all-digital hearing aid was developed in 1995, and since then the technology has improved significantly, ultimately to include wireless capability.
1985 – Transistor Hearing Aids
Now, imagine it’s 1985 and you’re seeking 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 founded until 1989.
You’d have to use the yellow pages, depend on referrals, or drive around the neighborhood to find a hearing care practice.
After reserving an appointment and having your hearing tested, your choices 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 higher power requirements, leading to larger batteries and larger hearing aids.
Additionally, without the advantage of digital technology, the hearing aid can’t differentiate between various frequencies of sound. Hearing aids receive inbound sound and the transistors behave 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 acquiring a hearing aid. Transistors haven’t been applied to hearing aids yet, so your choices are restricted to vacuum tube hearing aids.
Vacuum tubes consume more power than transistors, so the hearing aids call for 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 systems, making all inbound sound louder. The hearing aids cannot enhance speech and cannot filter out 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 convert sound into electrical currents that can be amplified.
With electrical amplification out of the question, your only possibility is mechanical amplification by concentrating and compressing sound into the ear, like what takes place when you cup your hands around your ears.
By 1650, devices were developed that concentrated incoming sound into the ears, and these contraptions were called ear trumpets. They were prominent devices 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 those with hearing loss for the next 250 plus years.
Let’s return to 2016. Throughout 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 come to be progressively smaller, lighter, and more effective and affordable.
They’ve also become better at distinguishing between different types of sound, and in amplifying only specified 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 major milestone in the history of hearing aids?
Will we eventually be able to improve natural human hearing, rather than simply restore it?