Understanding speech in large spaces is difficult. For someone sitting in the middle of an auditorium, a speaker’s voice has to travel a long distance to reach the person’s ears. The farther away a listener is from a speaker, the softer the speaker’s voice becomes.
In addition, it is more likely that random noises will interfere with hearing the speaker’s voice (has anyone had to cough just as the speaker said the punchline of a joke?). Distance also makes it less likely that the listener will be able to use visual clues (lip movement, facial expression) to supplement what is heard. It’s hard enough if the listener has normal hearing. A hearing loss only makes the situation worse.
These difficulties exist even when the speaker uses a microphone (the sound still has to get from the loudspeaker to the person’s ears). Hearing assistance in large spaces, such as theaters, lecture halls and churches can be accomplished with one of three systems: FM, Infrared and Induction Loop. In principle, all work in a similar way. The person speaking wears a transmitter microphone and the listener in the audience wears a receiver. The receiver sends the sound to the listener through headphones, or wirelessly to a person’s hearing aids from a neckloop to a telecoil that many hearing aids have. Because the sound of the speaker’s voice only has to travel a few inches to the microphone, and is then delivered directly to the listener’s ears, the quality of the sound is really good — like someone talking in a normal voice into your ear.
The difference in the systems is the mode of transmission from microphone to receiver. The FM system uses a radio wave, the infrared system uses a light beam, and the inductive loop system uses an electromagnetic field.
Audiologists are familiar with how all these systems work, and how they can work with personal hearing aids. We are strong advocates for the installation of one of these hearing assistance devices in any large meeting room. Many people, with or without hearing loss, could benefit from more consistently audible speech. We would like to assist our patients with the use of these devices, but because each system is a bit different, it helps if we know which system is in what auditorium.
We have the beginnings of a list of the facilities (auditoriums, churches, meeting rooms) in the area that have hearing assistance technology, which we would be happy to share with you. Please call an audiologist if you have questions about these systems or your hearing aids. If you know of a facility that has installed hearing assistance technology, please let us know so we can add it to our list.
Judith Albrecht is an audiology and owner of Albrecht Audiology in State College.