The Evolution of Hearing Aid Technology

Throughout human existence, people have struggled with being deaf or hard of hearing. Today, approximately 13% of Americans experience hearing loss in both of their ears. Fortunately, the technology to correct hearing problems has never been better. Exploring the history of hearing aid technology helps us appreciate the marvels of modern hearing aids.

Pre-Industrial Revolution: Acoustic Amplification

If you lived in the early 19th century or before, the availability of hearing devices was limited. The available technology was acoustic only, meaning that it relied on mechanical devices to amplify sound waves. For example, ear trumpets were a popular device to aid hearing. An ear trumpet was shaped like a funnel; when held to the ear, it collected sound waves and brought them to the ear. Unfortunately, ear trumpets offer only modest amplification of sound, making them a poor solution for the hard of hearing.

The First Electrical Hearing Devices

Inspired by the invention of the telephone, several 19th-century inventors sought to create hearing amplification devices. Thomas Edison experimented with a special transmitter that could boost the electrical signal in a telephone. However, the results were weak and not particularly helpful for the hearing impaired.

Soon, vacuum tube technology allowed greater amplification (up to 70 decibels) without as much distracting auditory feedback. The early vacuum tube hearing aids weighed more than 200 pounds and were larger than a filing cabinet! The hearing aid required the user to hold a receiver up to one ear, limiting the portability and utility of this option.

The Advent of Wearable Hearing Aids

The first wearable hearing aid was developed in 1938, with a small earpiece connected by wire to an amplifier-receiver and battery pack that the user would wear. By the 1950s, transistors were used to create hearing aids that could fit into the temple piece of a pair of glasses. So-called “hearing glasses” were considered less obtrusive than other available technologies and caught on widely.

Finally, in the 1960s, the first ear-only hearing aids were created. Popular behind-the-ear models were considered more reliable than hearing glasses. They became smaller and more unobtrusive over time. Although the sensitivity of the hearing aids gradually improved, many of these analog devices suffered from auditory feedback or distorted sound quality.

State-of-the-Art Hearing Aid Technology

Today, digital technology is the latest stage in hearing aid evolution. The latest devices can be finely tuned to each person’s unique needs. They also reduce the distortion that was problematic in many analog models. Now, digital hearing aids represent the largest share of the market.

Digital hearing aids are so sensitive that they can pick up additional background noise that can be distracting. The latest models have built-in algorithms to capture and eliminate that background noise, further improving sound quality. Other features, such as directional listening, allow the hearing aids to capture only the sounds you want to hear. With these novel technologies, today’s hearing aids are significantly better at replicating the natural sounds of your environment.