Sound Field Systems

Providing Intelligibility to the Learning Area

The typical Sound Field System includes a wireless microphone, which transmits speech to speakers strategically placed within a classroom. The right Sound Field Amplification System can improve the entire classroom-learning environment. For students, the right Sound Field System can lead to improved academic achievements, improved speech recognition skills and increased self-esteem. For teachers, it means reduced vocal strain as well as increased mobility and instructional versatility.

The key to success, however, is not amplification but intelligibility. There are a number of factors that determine the intelligibility in the learning area.

• A sufficient signal-to-noise ratio. The most important consideration is how clearly the student hears the teacher’s voice. A Sound Field System should amplify the teacher’s voice 8 – 10 dB above the classroom’s background noise.

• Even sound dispersion (sound levels) throughout the learning environment.

• Directional realism. That is, while the amplified voice is actually coming from the speakers, it sounds as if it is coming from the source (the teacher).

• A high ratio of direct sound energy to delayed or reverberant sound energy.

• Adequate bandwidth for speech.

• A lack of distortion from buzzes and rattles in the building and/or equipment.

To choose the right system, you must consider such variables as teaching style, seating arrangement, room size and room acoustics. Speaker and microphone specifications, as well as speaker placement within the room are also crucial.