Emerging Technology

Sounds Good

The benefits of voice amplification systems in the classroom.

• By Mike Raible
• 10/01/13

In the last decade, installation of sound enhancement systems has become a standard for many school districts. The advantages for investing in this technology appear to be well supported by increased student performance, reduced strain on teacher’s voices, and a classroom environment more conducive to learning.

A debate has been going on for some time between engineers involved with the development of design standards for classroom acoustics and proponents of voice amplification systems. To some extent, a classroom designed with appropriate attention to acoustics may not be dramatically improved by installing voice amplification equipment. On the other hand, advancements in sound enhancement technology offer considerable advantages to schools that have poor acoustical conditions in classrooms.

One point everyone seems to agree on is that children learn better when they can all hear what the teacher is saying, and teachers are better off when they do not have to strain their voice on a daily basis.

In most districts, controlling the acoustics in classrooms across the broad spectrum of school designs, ages and locations presents a formidable challenge. Following are several factors that contribute to this.

Hard surfaces. Although the American Speech-Language-Hearing Association (ASHA) recommends a reverberation time of .4 seconds, today’s classrooms with minimal sound-absorbing surfaces (carpet, tackboard, etc.) and more reflective surfaces (whiteboards, etc.) generally have higher reverberation time. Some have tested as high as 1.25 seconds. Harder surfaces reflect the sound and make speech less intelligible.

Ambient noise. Unit ventilators, heat pumps, lamp ballasts, projectors, computers and other students’ conversations all contribute to raising the ambient noise in the classroom. Activities outside the classroom also contribute: mowers, traffic, playgrounds and other environmental noise.

Sound quality. While many teachers can project their voice while delivering a lesson, many of the audio-visual devices used in the classroom may not have the same high quality sound. Small built-in speakers are less than optimal for delivering intelligible speech to a classroom full of students.

Functional hearing issues. The Mainstream Amplification Resource Room Study Project (MARRS) concluded that 20 to 25 percent of students had a minimal functional hearing loss (15 to 40 decibels). While the most severe of these are diagnosed and treated as special education conditions, many students simply miss a significant amount of academic instruction because of this condition.

Voice amplification systems designed specifically for classroom use offer school districts a practical solution. Among the many new products available, equipment typically includes an amplifier connected to several ceiling mounted speakers and microphones using infrared technology that prevents interference from equipment in adjacent rooms. The teacher’s microphone is worn as a pendant around the neck, and students have one or more wireless microphones that can be passed around.

Recent developments now include security alert functionality on the teacher’s pendant, enabling the office to be notified of an emergency. The speaker’s voice can be heard and recorded remotely by school administrators and emergency personnel. The latest systems also allow for connection to other audio-visual devices in the classrooms and the creation of podcasts from the lessons that are presented.

As for now, the application of this instructional enhancement is not consistent across the country. The state of Ohio, convinced that sound field amplification makes a difference, has mandated that all new school construction using state funds must include classroom amplification. Several other school districts, including Orange County Public School in Florida, Newton County School District in Georgia, and West Orange Public School District in New Jersey also install sound field amplification in all their new and renovated classrooms, but other districts have done little or nothing at all.

It certainly makes sense that if more students are getting the benefit of all the instruction being delivered their achievement increases. After all, would you expect a student who had missed 25 percent of school to do as well as a student with perfect attendance? Researchers also report a reduction of behavioral management issues in classrooms with amplification and a decrease in teacher absences of up to 13 percent. Ron Clark, author of the best-selling “The Essential 55” and cofounder of the Ron Clark Academy in Georgia says, “The audio system for the enhanced classroom, it’s a gift for teachers.”

One New Jersey elementary school teacher who uses the technology said, “I love this thing! I wouldn’t give it up!” Wouldn’t you like that reaction from your next facility improvements?

This article originally appeared in the School Planning & Management October 2013 issue of Spaces4Learning.