A hearing loop sends sound straight to hearing aids by magnetism. An amplifier drives a loop of cable laid round the room, and a hearing aid switched to its T (telecoil) setting picks up the signal, so the listener hears the speaker clearly without the background noise of the room.
This guide explains how a loop works, where businesses use one, and how to choose an amplifier. We supply hearing loop systems from Adastra; we do not install them.
How a hearing loop works, step by step
Sound goes in. A microphone (for example at a reception counter) or a feed from a PA system goes into the loop amplifier.
The amplifier drives a current round a loop of cable. The cable runs round the edge of the room, usually under the floor covering or along the skirting.
The current makes a magnetic field inside the loop that changes in step with the sound.
The hearing aid picks it up. Most hearing aids and cochlear implant processors have a telecoil. On the T setting it turns the magnetic field back into sound, straight into the ear.
Because the signal does not travel through the air, the listener does not hear echo, traffic or other conversations. That is the main benefit over simply turning a PA up.
Where businesses use hearing loops
Reception desks, ticket offices and service counters.
Meeting rooms, council chambers and lecture rooms.
Churches, halls, theatres and cinemas.
Museums and galleries, where a loop can also carry an audio tour.
Under the Equality Act 2010, service providers must make reasonable adjustments for disabled people, and a hearing loop is one of the most common adjustments for people with hearing loss. Display the loop sign so visitors know it is there.
Both have mic and line inputs with phantom power, tamper-proof volume, bass, treble and loop current controls, adjustable metal loss correction (useful in buildings with steel in the floor or walls), and alarm contacts. Their frequency response is 50Hz to 5kHz, which covers the range that matters for speech.
Testing the loop
After fitting, walk round the room with a loop receiver to check the signal is clear and even. The Adastra LR2 loop receiver is a beltpack with headphones that lets anyone, not just hearing aid users, listen to the loop. It can also turn a loop into a simple tour guide system for galleries and museums. A full installation should be commissioned to BS EN 60118-4 by a competent installer.
Common questions
Does a hearing loop work with every hearing aid?
It works with hearing aids and implant processors that have a telecoil (T setting), which most behind-the-ear and many other types do. The user switches to T or the loop program. Some very small in-ear aids have no telecoil.
Can people outside the room hear the loop?
The magnetic field spills a little beyond the cable, so loops in neighbouring rooms can interfere. Plan the loop layout with your installer if rooms are side by side.
What is the difference between a counter loop and a room loop?
A counter loop covers the small area in front of one service point. A room loop covers a whole room or hall. The Adastra LA-300 and LA-600 are room loop amplifiers.
Can I connect the loop to my existing PA system?
Yes. Both amplifiers have a line input, so the output of a mixer or mixer-amplifier can feed the loop at the same time as the speakers.
