Induction Field Loop Technology
The induction field phenomenon was discovered, like so many of our most important advances, by accident. It is a type of electromagnetic transmission that occurs when an amplified audio signal travels through a wire. The induction loop system consists of a wire that is installed around the listening area, and a special amplifier. The signal from the sound system is modified and circulated through this looped wire (transmitting antenna).
The resulting magnetic energy field is absorbed by a small coil of wire (receiving antenna) called a “T-Coil” or "telecoil" located inside hearing aids and cochlear devices.
Anyone with a telecoil compatible hearing aid can use the system without additional equipment. They simply switch their existing hearing aid to the “telecoil” position and they are wired directly into the sound system. And for those of us who do not yet wear hearing aids, a simple device with a set of headphones can be used to hear the audio from the Loop system.
Intelligibility is greatly increased because the distance between the speaker and the listener is bridged and background or environmental noise is almost eliminated; there is no echo or distortion produced by the room and sound system. It's like wiring the microphone directly into the hearing aid. The sound is mixed and adjusted by the hearing aid to compensate for each individual's hearing loss, giving them as close to true sound reproduction as possible with an assistive device.