by Neil Bauman, Ph.D.
A man wrote,
In our church we have an FM transmitter so that people who want to hear better can use an FM receiver with headphones. This works well for hard of hearing people without hearing aids. However, most use hearing aids, and when they put the headphones on over their hearing aids it sometimes makes a high-pitched noise and it is almost impossible to tell whose hearing aid is making the racket.
My question is, “Would a loop system work for us, or at least help us? The main auditorium is about 100 feet long and 50 feet wide.”
The high-pitched squealing sound you hear is feedback resulting from the headphones covering the microphones of the hearing aids (and thus directing the sound escaping from the ear canals back into the microphones in an endless feedback loop). That is one reason why, depending on the hearing aids, it is not a good idea to use headphones with hearing aids.
Fortunately, there is a much better way to couple hearing aids to your FM receivers. All it requires is that the hearing aids have t-coils built in (and most hearing aids do have t-coils now), and that you supply neckloops instead of headphones to those that have t-coils in their hearing aids. You can see/order a good neckloop here. Then, with the hearing aids in t-coil mode, the microphones will typically be disabled so you will not have that annoying high-pitched feedback anymore. (Blessed silence!)
Of course, you could install a room loop system in your church to replace (or supplement) your existing FM system and it would work very well. However, it would cost a fair bit more than just purchasing a few neckloops for those people that have hearing aids with t-coils in them. (I’m all for finding the most practical solution to fit your situation.) Those hard of hearing people without hearing aids would continue to use the receivers and headphones as they are doing now.
Incidentally, apart from the feedback issue, I think you’ll find that most hard of hearing people would much rather wear the less-visible neckloops than the very obvious headphones. As a result, more hard of hearing people likely will use your FM system to help them hear better.