Audio frequency induction loops

Are there situations where a loop is not suitable?

Yes, there are some. When the magnetic background noise (environmental noise) is loud, it may be impossible for anyone to receive a clear loop signal until the offending noise source has been removed. Where privacy is important, the loop needs to be carefully installed.

What are the alternatives to a loop system?

There are two other assistive listening technologies commonly used. Both operate by transmitting the audio signal to a receiver carried by the listener. These are commonly known as Infrared (IR) and FM carrier systems.

Are all hearing aids compatible with loops?

While not all hearing aids are fitted with a telecoil, many hearing aids can be fitted with a telecoil. Hearing advocacy organisations, such as Self Help for the Hard of Hearing (SHHH), acknowledge the benefits of a telecoil and actively promote telecoil usage.

We recommend the hearing aid user always discuss the telecoil option with their audiologist BEFORE selecting a hearing aid to ensure it has a telecoil. Cochlear implants are all telecoil compatible.

Hearing aids equipped with a telecoil have a switch allowing either “M” (microphone) or T (telecoil) operation. Some models may have a switch marked MT (microphone and telecoil) or MT (muted microphone and telecoil).

• The M (microphone) position is for ‘normal’ listening; that is, receiving sound via the microphone built in to the hearing aid.
• The T position is for receiving the sound via the telecoil, which is built in to the hearing aid.
• The MT position, which is provided on some hearing aids, allows for listening simultaneously to both airborne sound via the microphone and to transmitted sound via the telecoil.

What about digital hearing aids?

Digital hearing aids work in exactly the same way as analogue hearing aids in terms of induction loop use but you must make sure that the digital hearing aid has a ‘T’ switch position or ‘T’ program accessible by a program button or remote control. Check with your audiologist about this before you choose your aid.

Many digital hearing aids allow the relative levels between microphone and ‘T’ coil inputs to be adjusted by the audiologist. If the loop signal is too quiet or loud relative to normal microphone use, ask your audiologist to adjust it for you.

Do loops interfere with heart pacemakers?

Under normal circumstances, a correctly installed induction loop system does not interfere with heart pacemakers.  A minimum separation distance of two inches (50mm) should be maintained between loop cable and pacemaker to remove any potential for interference.

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