Assistive Listening Devices
Assistive listening devices (ALDs) include a large variety of devices designed to improve audibility in specific listening situations. Some are designed to be used with hearing aids or cochlear implants (CIs), while others are designed to be used alone. Many that are used in conjunction with hearing aids require a telecoil (T-switch).
While there are a bewildering variety of microphones, pickups, headphones, earphones, etc., that comprise assistive listening devices, they all have the same goal: to emphasize the ONE signal that you are interested in. That signal might be a faraway voice (e.g., a lecturer in an auditorium), or a relatively near signal that gets lost in other noise (e.g., listening to TV while others are talking nearby, or trying to converse in a restaurant).
Assistive listening devices can usually amplify a signal, but their primary purpose isnâ€™t to make a signal louder. Rather, they place a pickup (microphone) close to the sound source, so that it becomes louder compared to the other sounds in the environment. Assistive listening devices improve your ability to hear because they make the desired sound stand out from the background noise.
What Kinds of ALDs Are There?
There are two basic types of assistive listening devices; those intended for personal use and those intended for group use.
Who can benefit from an assistive listening device?
Anyone with some amount of residual hearing can benefit from an assistive listening device. A person who is able to converse one-on-one in a quiet room without lipreading would get a lot of benefit from assistive listening devices, because a properly used ALD can duplicate that quality of sound. People with less residual hearing will benefit from the use of an assistive listening device, because the device will provide extra lipreading clues.