Hearing Aids were a Pioneer in Electronics Miniaturization
When we talk about computers and other electronics, we can’t help but marvel at how small they’ve gotten. We’ve all seen someone look up a fact on their smartphone, only to mention how a computer that had a mere fraction of that capability used to take up an entire room.
While more and more processing power fits on smaller and smaller chips, it’s no surprise that the hearing aid industry is always at the forefront of taking advantage of new technology. Powerful DSP (digital signal processing) now drives each hearing aid unit, allowing your hearing aids to favor speech over background noise, assist with sound localization, and even communicate with other devices in your orbit. All this capability is powered by a tiny battery that will last all day. And the sound is captured by tiny microphones and amplified by tiny speakers that you would be hard-pressed to see with the naked eye, yet present astonishingly accurate sound quality.
Seeing what hearing aids have become today, it may not come as a surprise that hearing aids have driven miniaturization in electronics for over a century now. Prior to World War II, the hearing aid industry was the main locus of portable electronics technology.
Mechanical Hearing Aids
Prior to the advent of electronic hearing aids, “ear trumpets” were the most effective way to aid the ear for a person with hearing loss. Designers quickly discovered that larger trumpets were more effective, but moving about town with a large ear trumpet wasn’t to most people’s taste! George Tiemann & Co, a company that made surgical instruments, started designing ear trumpets that were less conspicuous. One was designed to look like a walking cane, while another featured a trumpet shape that would collapse telescopically into a small enough size to fit in a handbag.
Still, throughout the 19th century and up until very recently, there was a stigma associated with hearing loss and deafness. Deaf students, for example, were thought to learn better by following a practice called “oralism,” where they were instructed to sit in classes with normal-hearing students and learn to lipread, and to hide their hearing issues in public. Today we know that oralism is not effective at all. All persons learn best when taught in a way that accommodates their needs.
Telephone or Hearing Aid?
Unsurprisingly, those with hearing loss desired inconspicuous hearing aid devices that they could use without drawing attention to their disability. Mechanical hearing aids would never be able to meet the need for discretion that people felt at the time. In 1876, Alexander Graham Bell invented the telephone. His original device, with a receiver, a transmitter, and a battery, may have looked to an observer more like a hearing aid than a “telephone” in the sense we think of it. Almost immediately, people began using the telephone device as a hearing aid. In fact, a rumor circulated at the time that the device was actually invented as a hearing aid for a hard-of-hearing relative.
Vacuum Tubes
A race toward better amplification and smaller devices ensued. Thomas Edison’s carbon transmitter was replaced in 1908 by Lee De Forest’s vacuum tube. The vacuum tube was taken up by the military in World War I, improved upon and further miniaturized. Western Electric’s Audiphone hearing aid was released in 1922 and utilized vacuum tubes. Unfortunately, it was not very portable, weighing in at 220 lbs! It’s redesign for 1923 brought the weight down to 35 lbs, and the following year it came down to 7 lbs with the implementation of “peanut” tubes, a type of lightweight vacuum tube invented by the military. Vacuum tubes were the primary means of signal amplification for about 50 years, and are still used today in some musical applications for their unique sound.
Transistors
In the late 1960s, the transistor came into being and provided a much smaller and cheaper means of signal amplification. Hearing aids were able to shrink much further, providing the discretion that was still important in society at the time. Meanwhile, hearing aid companies, as well as deaf and hard-of-hearing people, worked to overcome the stigma surrounding hearing loss and deafness. While this stigma seems to finally be lifting, it has persisted for centuries and had no small part in driving the desire for smaller and smaller hearing aids—even when “smaller” sometimes also meant “less effective.”
The transistor is still the primary device used in sound amplification today, and has made great strides of its own since the 1970s. In fact, it’s so small that it has allowed space for computers to grow around it, while still being smaller than the hearing aids of the 1990s!
In addition to being smaller than ever, hearing aids today are more powerful than those big computers that used to take up a whole room, and available in a wide range of styles and sizes. They can offer discretion for those who want it, or function almost like jewelry. Models like the Phonak Audeo Paradise, Signia Styletto, ReSound LiNX, and Starkey Halo, just to name a few, are capable of providing long-lasting amplification to suit the needs of any lifestyle. They can be controlled via smartphone apps rather than direct contact with the hearing aid, and they can integrate with numerous other devices we use, so they can function just as much like earbuds as hearing aids.
