Assistive Listening Devices

Students who are deaf and hard of hearing may choose to wear personal amplification but personal amplification has limits in noisy environments such as the classroom. Assistive Listening Devices (ALDs) can improve the quality of the sound environment for improved access to sound.

ALDs improve the listener’s ability to pick up sound by bringing the source of the sound closer to the listener. These devices reduce the negative effects of background noise and distance. The listener can usually amplify the volume without amplifying the background noise.

This can help in the classroom when students want to listen to specific sounds such as the teacher's voice or a group discussion. Choosing the right combination of support (such as ALDs), the right classroom space and a support team will help the student's listening experience.

Boston Children's Hospital provides an excellent video on how to make ALDs successful in the classroom.

More about ALDs are available from other organizations:

Explore common ALDs used by deaf and hard of hearing students below.

Frequency Modulation (FM) Systems

A Frequency Modulation (FM) system includes a microphone/transmitter used by the speaker and a receiver used by the listener. The receiver can be a personal amplification device. The audio signal is transmitted by radio waves using different channels (frequencies). FM systems can be used for one-on-one meetings and in large group settings.

Watch this video "Samantha and her Fun FM and Hearing Aid Book!" created by a young deaf girl as she explains how her hearing aid and FM system works.

Induction Loop Systems

Induction loop systems are most commonly used in large group areas but may be installed in classrooms or large group areas such as the cafeteria or auditorium. The induction loop wire is installed around the area, often on the floor, and is connected to the speaker’s microphone. Listeners can use the telecoil in their hearing aid or cochlear implant to receive the signal.

Listen to a simulation! - HearingLoop.org demonstrates a simulation of the telecoil option on a hearing aid and an induction loop versus the microphone option on a hearing aid and no induction loop. To see the comparisons, click on the "M" and the "T" in each picture.

Infrared Systems

Infrared systems transmit sound using infrared light waves that are converted to a radio frequency. These frequencies are then broadcasted to receivers that convert the frequency to audio. Individuals will need earphones, headphones, or a hearing aid with a loop to receive sounds.

These systems are often used with TV sets and large group settings. Infrared systems are a good alternative to loop systems if a loop cannot be installed.

Personal Communication Devices

Soundfield Amplification Systems

Sound field amplification systems include a wireless microphone and loudspeakers set up around a space. The soundfield distributes and amplify the speaker’s voice through loudspeakers, placed strategically in the space. The soundfield can benefit all students but for the deaf and hard of hearing student, check if the student can comprehend the sound or if it can work with another accommodation in place.

Read this blog post "What is a classroom Soundfield system?" to learn how soundfields can benefit all students in the classroom.