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A Brief History of Hearing Aids

By Lindsay Hutton

A Brief History of Hearing Aids

Before hearing aids went digital and cochlear implants hit the market, the devices designed to help us hear went from the laughably primitive to top-notch in a relatively short slice of time. Why did hearing aid technology move so fast? Quite simply, those of us who can’t hear so well wanted better, smaller devices (preferably ones that could be hidden) – and fast. Here’s an abridged look at the history of the good, the bad and the outright bizarre of hearing aid devices.

Though the first Homo sapiens likely didn’t know that you could gain between five to ten decibels of sound if you cup your hand to your ear, we do know they figured out the concept behind it, as even gorillas in the wild have been seen doing it. In the mid-17th century, this decidedly lo-fi idea gave rise to “ear trumpets” -- tubular or funnel-shaped instruments designed to collect sound and direct it to the ear. And so it began.

Usually made from steel, wood, shells or animal horns, the idea of the ear trumpet soon moved toward “speaking tubes” 150 years later. Ever attach a string between two paper cups to chat with a friend as a kid? Similar thinking here: in the 19th century, funnels would be built into anything, from “acoustic” chairs, fans and vases to parasols, beards (!) and canes, and feature a tube leading to the direction of the ear. The longer the tube and the bigger the funnel, the better the sound.

The turn of the 20th century saw hearing devices entirely reborn by incorporating the newly discovered electrical technology. Developed in part by the Bell Telephone Company, the battery-powered carbon granule microphone opened up a whole world of sound for people with hearing loss by expanding the amount and range of sound amplification. Though the original microphones, batteries and amplifier unit were as big as a desk, the development of vacuum tubes in the 1920s allowed for a broader range of electrical signals to deliver not only more sound, but smaller, lighter units for users. Hearing aid devices at this time period were make-your-jaw-drop-expensive – batteries rarely lasted more than a day – costing a whopping $55 each in today’s money.

It was downhill from there. The 1930s and 40s gave way to snappier batteries and the invention of the transistor, giving users a unit that was actually wearable, about the size of a Walkman cassette player. One was still packing a load with aids developed at this time – the batteries weighed as much as a kilogram! The more refined hearing aid mavens even put their heads together with underwear designers to provide handy, slotted garters so people could wear them under their clothes, as most consumers still wanted to keep their aids relatively unseen.

By 1950, all three components of a hearing aid – battery, amplifier and microphone – were all streamlined into one relatively small unit weighing as little as 200 grams. In 1954, the very first eyeglass model hearing aid hit the market with a gallop, garnering over 50% of the market a mere 5 years later. The behind-the-ear (BTE) model arrived soon after for those not entirely sold on being bespectacled, and following on its heels were in-the-ear (ITE) models available for some, but not all, types of hearing loss in the 1970s. Many ITEs included adapted circuitry that could help filter out background noise.

As with many technological devices, aids surged ahead in the 80s; not only were they cheaper than ever before, but also began to include Digital Signal Processing (DSP). This technology allowed for hearing aid technicians to alter sound input and output, making a world of difference to users. For the first time, not only could hearing aids merely process sound, they could also generate it – making more useful sound for users with different types of hearing loss.

The 90s laid out even more technological watershed: two-channel sound, automatic and remote volume control, and Adaptive Speech Alignment (ASA). More recently, Bluetooth technology is the latest craze in hearing aids, leading to a wireless connection between hearing aids and cell phones and mp3 music players. For more information on the type of hearing aids available today, check out some more information here.

So what’s next? Hearing aids with satellite signals? Who can say? Not too long ago, many of us would be wearing a hearing aid in a hair accessory or a two-pound battery strapped to our leg to help us hear. To keep on top of the latest developments, talk to your audiologist at your next appointment.