Hearing aids are the best all-around solution for individuals with hearing loss, but other assistive devices can help people with hearing loss navigate specific communication demands. An FM system is an assistive listening device that makes it easier for people with hearing loss to hear what others are saying in noisy environment, like a theater, church, museum or other public place. This wireless system, also called a personal frequency modulation system, uses radio waves to deliver speech signals directly from the speaker's mouth to the listener's ears.
Components of an FM system
Think of a radio station. The disc jockey in the studio uses a microphone to speak to listeners who receive the signal through an antenna and play it through a set of speakers in their home or car. FM systems for people with hearing loss work in a similar manner. There are two basic components of an FM system.
Microphone: The speaker of interest wears a microphone that transmits their voice encoded in a frequency-modulated signal. The most common type, used often by teachers, is a lapel microphone that hangs around a person's neck. It should be about 6 inches away from the mouth in order to pick up the best speech possible. However, there are other types of microphones that may be used.
- Boom microphone: This microphone is about 3 inches away from the face, and is in the style of a headset that a customer service representative would wear.
- Directional microphone: This type of microphone makes it easy for the hearing aid wearer to get a direct focus on the person who is speaking. This cuts out background noise in loud situations. Directional microphones can be used by the listener, who will point the device in the ideal position to pick up noise when listening to others speak.
- Table microphone: Table microphones are best used in restaurants or conferences because they can pick up the voices of people around a table instead of one single voice.
Receiver: The listener wears a receiver that picks up the low-power radio signals from the microphone. These signals can usually be transmitted up to 50 feet. Often, the receiver is integrated into an individual's hearing aids (or cochlear implant) and the signal is delivered directly through their existing hearing device. If the FM system isn't integrated with a pair of hearing aids, there are two types of receivers that may be used.
- Ear level receivers:These are the smallest kinds of receivers, and are considered to be the most convenient for an individual who wears an FM system regularly but doesn't wear hearing aids.
- Body-worn receiver: Body-worn receivers are bulkier and are less convenient to carry around, but they are usually paired with traditional headphones making it easy to hear wherever you go. A body-worn receiver is great for short-term use or for use with children in a classroom.
Benefits of FM systems
People with hearing loss often struggle with clearly understanding speech in loud environments, even though their hearing aids are working overtime to pick out the speech signal in the presence of the background noise. To give your hearing aids a break and reduce your mental fatigue, you might consider purchasing an FM system for use when going out to restaurants, parties or other large gatherings. There are many benefits of FM systems.
Reduced background noise
People with hearing loss, and even those without, often have trouble hearing in situations when background noise gets in the way. FM systems reduce this noise and only amplify the voice of the speaker you are trying to hear.
Hearing from a distance
If you enjoy going to lectures or speeches, FM systems can be a great way to ensure that you are hearing every word that the person in front of you is saying. For example, if you are going to a grandchild's graduation who is speaking on behalf of his/her class, you will want to make sure that you understand what they are saying. Having your grandchild wear a compatible microphone will ensure that your FM receiver can reproduce the signal clearly for you, even in a large auditorium.
Just like any part of the body, if you are trying too hard to hear, you will suffer from mental fatigue. In fact, one of the symptoms of hearing loss is a feeling of exhaustion after spending a few hours in conversation. FM systems amplify speech signals in challenging environments so that you have the energy you need to do the activities you want to do.
FM systems in public settings
There is no reason to let your hearing loss stop you from enjoying the theater or going to the movies. Many large auditoriums have the capabilities to provide excellent sound quality without interference. FM technology in a theater setting allows you to use your hearing aid with an FM receiver, and the signal goes straight through to the device so that the sound is clear. For those who don't wear hearing aids, FM systems paired with traditional headsets may be available for you to wear during the show. Don't be shy--ask at the box office.
FM systems for children
Children who are experiencing hearing loss may struggle with being able to hear properly in the classroom. This can hinder their education and cause them to lag behind because they cannot understand what the teacher is telling them. Some classrooms use a sound-field amplification system so that all children may benefit from an amplification of the teacher's voice. A sound-field amplification system uses a microphone to amplify the speaker's voice through a loudspeaker system that is positioned strategically in the classroom. This way all students can benefit from the amplification, and those with hearing loss are freed from the burden of wearing a special receiver.
An FM system is especially important for children with hearing loss as they attend school. It ensures that these children receive consistent speech signals even when they aren't looking at the teacher or when the teacher is moving around. A microphone can also be passed around to other students as they participate in a lesson so that the child with hearing loss has an opportunity to hear those comments and questions as well. An FM system at home gives children with hearing loss a better opportunity to interact during daily activities with their families, as well as enjoying trips to the zoo or park, or driving in a car.
- FM Systems, American Speech-Language-Hearing Association, http://www.asha.org/public/hearing/FM-Systems/