Diverse Environments Pose Challenge for Good Sound
Apr 4, 2007 11:49 AM,
By Linda Seid Frembes
The diverse environments in a school setting pose constant challenges to administrators who are evaluating AV products for their school—particularly audio systems. From classrooms to hallways, cafeterias to auditoriums and gymnasiums, these varied settings cannot be addressed using a cookie-cutter design. Instead, schools should look at each type of room as its own application.
“In K-8, the applications are still about classroom announcements as well as public address (PA) systems for hallways,” says Dave Raneses, brand manager for EAW Commercial, a loudspeaker manufacturer specializing in loudspeaker products for the commercial, institutional, and industrial markets. “At that age, it’s about getting your message to them. In high school [9-12], the audio concept changes a bit, with systems that are more in tune with current technology and applications. At this level, schools are willing to spend money to get better sound.”
In higher education, the AV technology is dictated by the budget amount and whether the university receives state funding. Raneses has found, in general, that more higher-education institutions are willing to increase their spending on current audio technology. “In the higher education market, ceiling speakers tend to be the bulk of the purchase,” he says. “Because institutional installs tend to be large-scale, ceiling speakers are a good aesthetic choice that doesn’t compromise performance. We also go beyond the box and try to educate the institution about digital signal processing and amplification requirements.”
Educating the educators is a constant process. Each year, shows like the upcoming Educomm conference are heavy on educational programs about using AV technology in schools. “In the K-12 market, decisions are often made by committee,” Raneses says. “Committee members often lack the resources to learn about audio and are missing the basic knowledge about selecting the proper gear, the process of integration, and how different environments can affect sound. You can’t change the physics of a room.”
School environments like cafeterias and gymnasiums may seem similar—large, open spaces with seating to accommodate a large number of kids—but are actually acoustically different. “To compound the issue, both types of rooms are often used for multipurpose activities so it can be a big challenge to find an audio system that sounds good,” Raneses says. “Gyms, for example, can have different applications for the same space, like a pep rally in the afternoon and a basketball game at night.”
In a paper called “Kids + Cafeteria = NOISE!” presented by Joseph F. Bridger of Stewart Acoustical Consultants at the 144th ASA Meeting in 2002, Bridger noted: “Those who study the ability to understand speech in noise often use what is called ‘cafeteria noise’ as the noise source. It is a recording of many people talking at the same time. This is especially true of the school cafeteria. Parent Teacher Associations (PTAs) and others call acoustical consultants looking for answers to this problem. Some cafeterias exceed the OSHA noise level of 85dBA and causing cafeterias to begin accumulating noise dose.”
But with cuts in state funding, K-12 educators feel the pressure to spend limited budget dollars on new books rather than loudspeakers. However, research study after research study has confirmed the importance of speech intelligibility in the classroom and beyond. Most famously, the MARRS Study by the National Diffusion Network (NDN) found that using soundfield amplification in the classroom enhanced oral instruction, lessened teacher voice fatigue, and improved student academic achievement. “Amplification of the teacher’s voice above background noise was provided so that all students are able to hear and listen to the teacher clearly—no matter where the teacher is or moves to in relation to the where the student sits,” the study says.
Raneses encourages school administrators to go online and look at the different audio products available to the market today. “Go speak with other schools who have installed audio systems—and most importantly, go listen to those systems,” he says. “I would also advise that schools talk to an audio consultant. Consultants are not necessarily tied to one manufacturer; their goal is about doing the best job. They are aware of everyone’s products and can give advice on what would best fit the application. Overall, technology should be affordable, reliable, easy to maintain, and provide value to the educational experience. Products that meet these basic requirements often mean that the money was wisely spent.”