We may take it as a given that our hearing aids are scarcely detectable, can be managed with our cell phones, and can distinguish between speech and background sound. What we might not realize, however, is that those functions are the results of 400 years of research, design, and enhancement.
Even 5 years ago, hearing aids could not yield the clarity of sound produced today. To understand why, let’s follow the history of hearing aids—starting 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 open up an internet browser, search for a community hearing care professional, complete a brief form, and schedule a consultation.
At your hearing assessment, your hearing is screened using sophisticated computer technology that accurately assesses your hearing. Then, with the assistance of your hearing care specialist, you choose a hearing aid that meets your requirements from a vast range of models.
Then, your hearing practitioner programs your new hearing aids to amplify only the sounds and frequencies you have difficulty hearing, which results in crystal clear sound without distortion.
If you told 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 short, digital technology.
For the majority of their history, there was no way for hearing aids to discern between different sound frequencies. Hearing aids would amplify all inbound sound, including background noise, creating distorted sound.
The digital revolution addressed that issue. With digital technology, all information can be converted, saved, and manipulated as permutations of 0’s and 1’s. Digital technology enabled hearing aids to transform sound frequencies into digital information, which could then be classified according to which sounds should be amplified (speech) and which should be suppressed (background noise).
The first all-digital hearing aid was produced in 1995, and since that time the technology has improved dramatically, eventually to include wireless capability.
1985 – Transistor Hearing Aids
Now it’s 1985 and you’re planning to treat your hearing loss. You can forget browsing for a local hearing care provider on the internet because the first commercial internet service provider won’t be founded until 1989.
You would need to use the yellow pages, depend on recommendations, or drive around the neighborhood to find a hearing care practice.
After reserving an appointment and having your hearing analyzed, your choices for hearing aids are very limited. Without the microprocessor and digital technology, hearing aids were manufactured with a series of transistors. This adds size and increased power requirements, resulting in larger batteries and larger hearing aids.
Also, without the advantage of digital technology, the hearing aid cannot 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 practically impossible.
1940 – Vacuum Tube Hearing Aids
It’s 1940 and you’re thinking about acquiring 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 big, heavy, and awkward.
And once again, without digital technology, the hearing aids can only act as basic amplification systems, making all inbound sound louder. The hearing aids cannot enrich speech and can’t filter out 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 convert sound into electrical currents that can be amplified.
With electrical amplification unattainable, your only alternative is mechanical amplification by focusing and compressing sound into the ear canal, much like what happens when you cup your hands around your ears.
By 1650, products were developed that concentrated incoming sound into the ears, and these contraptions were labeled ear trumpets. They were prominent gadgets 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 grown from mechanical amplification devices to electrical amplification devices, from vacuum-tube-based to digital-based. They’ve come to be considerably more compact, lighter, and more effective and affordable.
They’ve also become much better at differentiating between various types of sound, and in amplifying only specific types of sound (such as amplifying speech while suppressing background noise).
Each generation of hearing aid has generated a major enhancement over the previous generation. The question is, what’s the next major benchmark in the history of hearing aids?
Will we eventually be able to enhance natural human hearing, rather than simply restore it?