We may take it for granted that our hearing aids are hardly detectable, can be controlled with our smart phones, and can differentiate between speech and background noise. What we may not realize, however, is that those features are the results of 400 years of research, design, and improvement.
Even 5 years ago, hearing aids could not generate the clarity of sound produced today. To understand why, let’s trace the history of hearing aids—beginning today and moving backwards—to observe 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 looking to treat your hearing loss. You open up an internet browser, search for a nearby hearing care professional, submit a brief form, and schedule a consultation.
At your hearing assessment, your hearing is analyzed using advanced computer technology that accurately assesses your hearing. Then, with the assistance of your hearing care practitioner, you select a hearing aid that suits your requirements from a wide range of models.
Then, your hearing specialist programs your new hearing aids to amplify only the sounds and frequencies you have difficulty hearing, bringing about 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 make 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 amplify all inbound sound, including background noise, creating distorted sound.
The digital revolution addressed that challenge. 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 identified based on 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 that time the technology has improved significantly, eventually to incorporate wireless functionality.
1985 – Transistor Hearing Aids
Now it’s 1985 and you’re looking to treat your hearing loss. You can forget about 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 need to use the phone book, rely on referrals, or drive around the neighborhood to find a hearing care practice.
After booking a consultation and having your hearing examined, your choices for hearing aids are very restricted. With no microprocessor and digital technology, hearing aids were developed with a series of transistors. This adds size and increased power requirements, leading to bigger batteries and massive hearing aids.
Also, without the benefit of digital technology, the hearing aid can’t distinguish 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 loud room, speech recognition will be just about impossible.
1940 – Vacuum Tube Hearing Aids
It’s 1940 and you’re looking into buying 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 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 enhance 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 out of the question, your only option is mechanical amplification by concentrating and compressing sound into the ear canal, much like what takes place when you cup your hands around your ears.
By 1650, products were developed that concentrated inbound sound into the ears, and these contraptions were named ear trumpets. They were prominent devices 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 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 become increasingly more compact, lighter, and more effective and affordable.
They’ve also become much better at differentiating between different types of sound, and in amplifying only particular types of sound (such as amplifying speech while suppressing background noise).
Each generation of hearing aid has made a major improvement over the previous generation. The question is, what’s the next major milestone in the history of hearing aids?
Will we soon be able to improve natural human hearing, rather than merely restore it?