Assistive Listening Devices
Hearing assistive technology such as audio loops (or hearing loop), FM, and infrared systems are like binoculars for the ears and work with or without hearing aids. These are assistive listening devices that help get past the obstacles to hearing. They can overcome the problems encountered when the source of sound/speech is at a distance or when there is a great deal of noise. There must be a microphone to pick up the speech, TV signal, radio, etc. at the source. The mic is connected to an amplifier/transmitter. A receiver on the listener gets the clear signal. The transmission modes and receivers take several forms.
The audio or hearing loop is a wire that circles a room and is connected to the room’s sound system. The loop transmits sound electromagnetically. The electromagnetic signal is then picked up by the telecoil in the hearing aid or cochlear implant. To use a hearing loop, one easily flips the telecoil switch on the hearing aid or cochlear implant. No additional receiver or equipment is needed. Using a telecoil and hearing loop together is seamless, cost-effective, unobtrusive and you don’t have to obtain extra equipment. If the hearing aid does not have a telecoil, a set of headphones with a special receiver can be worn.
An infrared system uses invisible light beams to carry sound from the source to a personal receiver. (The sound source must be in the user’s line of sight.) Different types of attachments may be connected to the personal receiver such as a neck loop (a wearable audio loop) or a behind-the-ear silhouette inductor. The telecoil then picks up sound from the receiver via the attachment.
An FM system works similarly, but sound is conveyed though radio waves to a personal receiver attached to your hearing aids or in a set of headphones having an FM receiver. FM Mic/transmitters can be simple with just an omnidirectional microphone that a talker wears to very sophisticated with directional microphones and different beam-forming settings.
Bluetooth is another form of sending a signal from one place to another, and it requires a mic/transmitter and a Bluetooth receiver that links with your hearing aids. In most cases, an additional wireless receiver called a streamer is required and is worn by the user. Bluetooth TV transmitters, cell and land line phone links and mini microphones will bring the signal to your hearing aids in stereo. One manufacturer has a direct Bluetooth link with no streamer required.
These devices help us to hear and understand better in many situations where acoustics are poor, background noise is bothersome, and there is a long distance from the speaker.
In public places such as theaters, listening systems are required under the Americans with Disabilities Act (ADA) to make programs and services accessible. But, you must ask for the accommodation.