Assistive listening device
An Assistive listening device (ALD) is used to improve hearing ability for people in a variety of situations. A common usage is to aid people who are hard of hearing (HOH). by amplification and better sound to noise ratio (SNR). The ALD may be used to help HOH people hear televisions and other audio devices and also to help people hear speech through public address (PA) systems such as in synagogue or at a lecture.
The assistive listening device usually uses a microphone to capture an audio source near to its origin and broadcast it wirelessly over an FM (Frequency Modulation) transmission, IR (Infra Red) transmission, IL (Induction Loop) transmission, or other transmission method. The person who is listening may use an FM/IR/IL Receiver to tune into the signal and listen at his/her preferred volume.
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