New Technologies

Hearing instrument technology has come a long way in the last few years, thanks to the computer microchip and digital circuitry. Here are some of the latest innovations.

Digital Technology
Why does music from a cd sound more crisp, clear, and distortion-free than music from a record or tape? The answer, at least in part, is the difference between analogue and digital sound processing.

Digital hearing instruments have one or more microchip processors inside them that convert analogue sound waves into the zeros and ones of computer language. Sound in this format can be processed more quickly and more efficiently than analogue sound waves; in fact, incoming sounds are sampled at a rate of a million or more times per second. The digital instrument’s circuitry analyses these sound levels and frequencies, manipulating them to provide a more efficient match to an individual’s hearing profile.

For example, a person with hearing loss may have trouble hearing soft sounds, but when some sounds are amplified even a small amount, they become uncomfortably loud. Hearing instruments with digital compression circuitry are able to stratify incoming sounds, detect those that need amplification from those that don’t, and process the sound accordingly.

Programmable Technology
Digitally programmable hearing instruments, which are different from fully digital instruments in that they’re not equipped to process all incoming sound digitally, offer the very useful benefit of being able to sculpt sound to fit a particular individual’s unique hearing profile, and can be reprogrammed if there are changes in hearing loss. Programmable instruments can be set up with multiple channels, enabling you to preset and store several different programs, each sculpted to a particular set of sound environments. You can then select the appropriate program using a button or remote control unit: normal conversation, concert hall, office, or telephone, for example.

Feedback Reduction Technology
Feedback has long been a problem for hearing instrument wearers. Now we know a lot more about feedback, and have developed ways to deal with it. Feedback happens when amplified sound waves escape back out through the ear canal and are then re-amplified by the hearing instrument—resulting in the high-pitched squeals that set your teeth on edge. Smaller, in-the-canal styles of hearing aids place components closer to the eardrum, preventing sound waves from escaping, thereby reducing, and often eliminating, feedback. Some new instruments are also able to detect these sounds before they become audible and cancel them out, greatly reducing this frustrating problem.