Used by millions of hearing impaired individuals each and every day, hearing aids have never before been so compact and comfortable. Their versatility and efficiency is thanks in large part to their long and varied history. Thanks to immense leaps in technology for hearing aids over the last two centuries, everyone should take a step back to see how far the technology has actually come. Here we explore the long yet successful evolution of hearing aids throughout three distinct periods and technology levels.
Early Hearing Aids
The earliest hearing devices did little to bring out the sound and could only give benefits in terms of incremental acoustic improvement to those who needed it. Ear trumpets were the first sound amplifiers but they weren’t consistent in size and they were shaped like big horns that could capture and amplify sounds that were picked up. The device would simply funnel the sound into the inner ear so the user could have a better chance of hearing than they had before.
Carbon Hearing Aids
It was only in the late 19th century that the first true hearing aids were emerged onto the technology scene, thanks in large part to Alexander Graham Bell’s telephone invention. This formed the cornerstone of establishing the carbon hearing aid, which basically used a carbon microphone in relation with a magnetic receiver and battery. What would happen is that sound would hit the outside of the microphone, which consequently redirected the tiny carbon pieces in the hearing aid. Those would then press against the diaphragm in relation to how much sound was generated; as such, the pieces moving through the diaphragm would react similarly to sound waves. This approach features significant drawbacks, though, because the sound of the carbon going through the hearing aid would give off interference and low quality sound, with the ability to only pick up on a few frequencies. As a result, it could help people with limited hearing loss but that was about it.
Vacuum Tube Hearing Aids
Vacuum tube hearing aids weighed seven pounds but they were the greatest invention up to this point for the hearing impaired community. They emerged just before the true electronic hearing aids did in the 1920s. Bell Labs improved on the design later, creating the invention of the first transistor for use in hearing aids. Using the transmitter from a telephone to convert sounds gathered into electrical signals, these would then manifest themselves into amplified sound as they moved through the receiver end. On the brink of the electronic hearing aid design, this invention convinced investors and customers alike that new technology could be used for the sake of better hearing health.