Gym Uses AV To Address AcousticsA Midwestern university's athletic center installs a zoned audio system to enhance sound intelligibility. 4/29/2006 8:04 AM Eastern
Gym Uses AV To Address Acoustics
A Midwestern university's athletic center installs a zoned audio system to enhance sound intelligibility.
The large field house at the University of Wisconsin-Whitewater's Williams Center features 48 JBL loudspeakers, carefully positioned using EASE software.
Credit: Courtesy of the University of Wisconsin-Whitewater
CHALLENGE: Design-build a university athletic center audio system that provides clear, intelligible signals for multiple types of events, despite a less than ideal acoustical environment.
SOLUTION: Use a computer program to simulate where speakers can be placed to best serve those on the court and off, zoning different areas to minimize interference.
With the crowd roaring and feet stomping, the noise is deafening when the Warhawks of the University of Wisconsin-Whitewater (UWW) sink that last-second basket. No one really cares if the announcer's voice is lost in the din. They do care, however, when the scene changes and that same gymnasium is decked out in school colors for commencement. Every parent wants to hear the name of their graduate ring throughout the room, loud and clear.
The noise and echo created by concrete block walls, high ceilings, steel beams, and hard shiny floors of gymnasiums have always been a challenge for audio designers, but there's a way to overcome that “cardboard box” effect. “A gymnasium can be an acoustical nightmare,” says Susan Lewis, CEO of AV integration firm Lewis Sound & Video Professionals in Waukesha, WI. “A newly constructed gymnasium may use more acoustically friendly materials than gyms built years ago, but it's still a great big box.”
The University of Wisconsin-Whitewater expanded and renovated its Williams Center athletic facility in 2001. The project was an effort to meet increasing demand for athletic accessibility from its student body. “The Williams Center is one of our primary recruiting tools — not only for athletes, but for the general student body as well,” says Gary Harms, UWW director of recreation sports and facilities. “Participation numbers have almost doubled since it opened.”
The new 57,000-square-foot field house has four side-by-side basketball courts with a surrounding running track. A weight room/fitness center, athletic training room, classrooms, and office space are also housed nearby. A trio of gymnasiums — for gymnastics, volleyball and wrestling — were renovated in the existing part of the building. Lewis Sound & Video Professionals drew the task of designing and installing audio systems in the three main areas of the center: the field house, the weight room, and the volleyball arena.
“We wanted something that sounds good for athletic events and recreational use,” Harms says. “These are all separate venues within one big facility here, and we wanted to be sure they sounded crisp and clean.”
A big empty room made of unfriendly materials can bounce sound around like a basketball, but the field house at the Williams Center offered some options. “Essentially the more objects that can be placed in a room, the more reflective surfaces there are,” says Henry Lewis, acoustical consultant at Lewis Sound & Video. “Those objects start to quiet down a room that's otherwise a gigantic shoebox without barriers anywhere. Fortunately, this room was broken up by enough objects — like dividing curtains — that the acoustics weren't as bad as some.”
Another important factor is that a seated audience is much more sound-absorbent than empty bleachers or a hardwood gym floor. If you can direct the sound only at the audience, you'll avoid a lot of unnecessary reverb. Lewis says that “the last thing you want to do is put sound into the full court if you're only using half, because that extra sound is simply going to bounce around.”
One of the biggest variables is the size of the crowd. Basketball games are a big draw, but unless the volleyball team is winning, the bleachers can be half empty. “People help,” Lewis says. “It's the sparsely populated games that are difficult because that sound echoes off the bleachers and causes intelligibility problems.”
EASE into it
Using the EASE (Enhanced Acoustical Simulator for Engineers) program by Software Design Ahnert (SDA) of Germany, Lewis input the dimensions of the field house and the acoustical materials onsite to predetermine the best configuration for the speakers. “The EASE software shows us where we need sound and how much, but it doesn't choose the speakers,” Lewis says. “That's where knowing the product and a little trial and error come in. There may be more than one speaker that works, and then you pick the one that's most cost effective.”
Lewis chose 48 15-inch JBL 2155H loudspeakers to be hung from the ceiling of the field house, and powered them with 12 Crown K1 amplifiers.
But keeping all of the speakers on at all times isn't the best solution for rooms often used for other events. “These have to be multi-functional spaces,” Susan Lewis says. “Athletics is a huge money maker, but the university can't be myopic. They can't say that sporting events are the only thing that exists anymore.”
In fact, these new facilities often double as locations for community meetings, or graduation ceremonies where large crowds are expected. For that reason, Lewis positioned all 48 speakers to fire directly down onto the playing surfaces of the field house, but zoned them so that when separate events are held on the courts and the fabric walls are lowered, the cross-court interference is minimal. “Curtains don't completely stop sound from getting from one side of the room to the other,” Lewis says. “But the more reflective surfaces you've got, the better.”
Lewis also programmed four presets on the Peavey MediaMatrix Miniframe 108nt-40 DSP system to make it easy for the field house staff to pick the right zones for each event. In essence, the MediaMatrix is a proprietary computer equipped with digital processing cards and a Peavey MM8840 digital interface outboard break-out box. Password-protected for security, the presets zone the speakers into useable configurations. A big basketball tournament might use one preset to keep all speakers on all the time. But a track meet might need only the speakers over the track to be firing, so the inner court speakers can be turned off while the audio system in the nearby volleyball arena is turned on.
A long hallway separates the two gymnasiums, but Lewis tied the two audio systems together because the volleyball arena also serves as the athlete warm-up area during track meets in the field house. “We tied the sound systems together, so you can hear the next event and the athletes can warm up and know what's going on in the field house,” Harms says.
Mobility is another important factor during sporting events — especially for referees and announcers. To provide portable audio support, Lewis also added several Audio-Technica AT-86007U wireless microphone systems throughout the facilities.
Built 25 years ago, the volleyball arena still needs new acoustical treatments on walls and ceilings before the 18 JBL 2155H loudspeakers Lewis installed in the ceiling can reach their maximum potential, Harms says. “When there are a lot of people in there it helps absorb some of the sound,” he says. “But when it's empty or we use it for classes or practices, it's hard to hear because of the nature of the facility.”
The new speakers and the Peavey Media Matrix X-Frame Miniframe processor considerably improved the facility's audio clarity, but it will be even better once the new panels are installed later this summer.
In the weight room, a slightly different configuration was chosen. The room's 12 JBL 2155H loudspeakers are complemented by 6 JBL Control-28T-60 loudspeakers that serve a second level of the room where the larger speakers can't reach. The weight room system is used primarily to feed background music from various rack-mounted sources, including a Denon Professional DN-770R cassette recorder and DCM-30P CD player and a TEAC PTR-400 AM/FM tuner, while students work out.
Because school gymnasiums are often the largest venues available at graduation time, they also become the room of choice for such events. Presets for commencement ceremonies, however, often require more than simple on/off choices.
“For graduation, they set up a stage at one end of the room and reduce the level of the loudspeakers right over the stage,” Lewis says. “Then they delay them sequentially farther and farther back into the room to give a realistic presence to the speakers on the stage. It's to provide phase coherency, so the intelligibility of the amplified signal remains un-degraded.” In essence, this ensures that people in the back can hear as well as the people in the front.
Safe and sound
For the sake of security, all presets and the MediaMatrix control are password-protected and stored in an equipment rack in a control room just off the main court area, along with the AM/FM digital tuner, audio cassette recorder, and CD player. Once accessed, the main screen gives the operator four choices. The first acts as a panic button and mutes the entire speaker system, while the second button opens the preset choices. The third and fourth buttons provide access to system diagnostics and schematics.
“For as large a facility as this is, people can't believe the sound quality,” Harms says. “It's just a large, open space without interior seating or anything to absorb the sound, but it's really crisp and clear.”
Of the Williams Center AV system's $180,000 price tag, $125,000 was spent on the field house alone. It takes money to build these impressive new facilities, and whether it's public funds or private, the schools are motivated to make the best use of these new buildings. With the help of software simulations and a solid working knowledge of what AV technology can do today, the acoustical challenges once presented by gymnasiums can be brought under control, and the spoken word can be heard above the cheering crowd.
Wendy Ellis is a freelance writer based in the northwest suburbs of Chicago. She can be contacted at firstname.lastname@example.org.