We may take it for granted that our hearing aids are barely visible, can be managed with our cell phones, and can differentiate between speech and background noise. What we may not realize, however, is that those capabilities are the results of 400 years of experimentation, design, and improvement.
Even as early as 5 years ago, hearing aids could not generate the clarity of sound generated today. To understand why, let’s follow the history of hearing aids—starting today and travelling backwards—to see 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 searching to treat your hearing loss. You launch an internet browser, search for a community hearing care professional, submit a quick form, and arrange an appointment.
At your hearing exam, your hearing is tested using advanced computer technology that precisely evaluates your hearing. Then, with the help of your hearing expert, you select a hearing aid that complements your requirements from a wide range of models.
Then, your hearing expert 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 render it possible? In a nutshell, digital technology.
For the majority of their history, there was no way for hearing aids to differentiate between different sound frequencies. Hearing aids would enhance all incoming sound, including background noise, producing distorted sound.
The digital revolution resolved that problem. With digital technology, all information can be altered, stored, 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 sorted in accordance with 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 tremendously, ultimately to include 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 web because the first commercial internet service provider won’t be established until 1989.
You would have to use the phone book, depend on referrals, or drive around the neighborhood to find a hearing care practice.
After scheduling an appointment and having your hearing screened, your options for hearing aids are quite limited. Without the microprocessor and digital technology, hearing aids were created with a sequence of transistors. This adds size and higher power requirements, leading to bigger batteries and larger hearing aids.
Also, without the benefit of digital technology, the hearing aid can’t differentiate between various frequencies of sound. Hearing aids receive inbound sound and the transistors behave as basic amplifiers, amplifying all sound. So if you’re in a loud area, speech recognition will be just about impossible.
1940 – Vacuum Tube Hearing Aids
It’s 1940 and you’re interested in purchasing a hearing aid. Transistors haven’t been applied to hearing aids yet, so your choices are confined 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 basic amplification devices, making all inbound sound louder. The hearing aids cannot enrich speech and can’t remove 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. That means no way to convert sound into electrical currents that can be amplified.
With electrical amplification unattainable, your only possibility is mechanical amplification by concentrating and compressing sound into the ear, as with 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 devices were labeled 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 readily available to individuals 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 progressively more compact, lighter, and more efficient and affordable.
They’ve also become better at differentiating among different types of sound, and in amplifying only selected types of sound (such as amplifying speech while repressing 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 enhance natural human hearing, rather than simply restore it?