What’s a Hearing Loop?
Also called an induction loop, it’s a loop of wire connected to an electronic sound source that transmits that sound clearly and directly to the telecoil in a hearing aid or cochlear implant. Although digital hearing aids have significantly improved over the last decade, they still don’t restore hearing to normal. A hearing loop eliminates most background noise and significantly improves signal-to-noise ratio.
“I can hear, but not understand!”
Sound familiar? Most hearing aid users need an improved signal-to-noise ratio. They need to increase signal level and/or decrease noise level, especially in reverberant places such as auditoriums or churches. Hearing aids equipped with T-coils and coupled with hearing loops can minimize this problem.
Where Are Hearing Loops Normally Used?
Hearing loop systems can be installed anywhere people gather, and greatly enhance the way people who need hearing assistance experience their world. A typical installation site is any space where background noise and/or poor acoustics compete with the primary sound source, making speech less intelligible, such as:
Countertop hearing loop units work well in transient locations such as:
- Medical consultation areas
- Retail checkout counters
- Ticket windows
- Drive-thru and pick-up windows
- Museum exhibits
How Do Hearing Loops Work?
The loop system consists of an electronic sound source, such as a microphone or a PA system; an amplifier, which processes and sends the signal to the loop cable; and the loop cable, a wire placed around the perimeter of an area to act as an antenna that sends the magnetic signal to the hearing aid.
A hearing loop provides a magnetic, wireless signal that is picked up by a hearing aid when it is set to “T” (telecoil). All cochlear implants, most behind-the ear-hearing aids, and all but the smallest custom in-the-ear instruments can be equipped with a T-coil, a small copper coil that receives electronic signals.
The “T” setting on a hearing aid is for receiving sound via the telecoil, which is built into the hearing aid. (Most hearing aids can be retrofitted with a T-coil via a “boot.”) When a hearing aid user selects the “T” setting in the presence of a hearing loop, he or she hears the sounds spoken into, for example, a microphone — instead of all the ambient noise. Sounds are heard clearly, without distortion or background noise pick-up, resulting in improved speech understanding.
The T-coil program is accessed by pushing a button on the hearing aid, or by using a remote control to switch to T-coil mode. Audiologists often recommend the T-coil setting for listening on the telephone without feedback or whistling. If you have this “telephone program” (where the microphone is turned off), you most likely have a T-coil.
Sometimes a T-coil is installed in a hearing instrument but not activated. Check the instruction booklet to see if your hearing instruments have telecoils, or contact your audiologist about the presence and activation of telecoils in your HAs.
Today’s new lighting and flat-screen monitors rarely have an influence on induction loops. Occasionally, T-coils are susceptible to interference (low-pitched buzzing) around malfunctioning or older fluorescent lights, conventional CRT (non–flat screen) computer monitors and TVs, electrical wires, dimmer switches and transformers.
Information courtesy of Dr. Juliëtte Sterkens, Audiologist, Wisconsin Hearing Loop Advocate