The situation facing dB Audio & Video's system advisor Keith Armstrong was every acoustic contractor's worst nightmare: The good people of Meadowbrook Baptist Church in Gadsden, Alabama had decided to ditch their old, 550-seat sanctuary in favor of the only larger room they possessed in order to accommodate their happily burgeoning numbers. No longer would the washed-out squeaks of sneakers or the low rumble of basketballs against backboards reverberate in the echoey din of Meadowbrook's gymnasium. It was to be their new sanctuary. And Armstrong had to make it sound that way.
The gymnasium was a large 120 ft. x 80 ft. x 22 ft. box covered with reflective surfaces, and Armstrong measured its reverb time at 7.5 seconds. However, the church determined they could place a generous stage along one of the long walls and still accommodate 900 church members. Since the church was operating on a tight budget and since Armstrong was told that some of their members owned metal fabrication companies and would be willing to donate their time and expertise, he started by drafting plans for diffusion panels to cover both of the shorter walls. The church took the plans and, using church labor and a modest outlay for materials, built the diffusion panels themselves.
"The diffusion panels would help kill the rather extreme flutter echo," Armstrong explains, "but there was still a massive slap-back echo from the back wall to the stage." To combat the problem, dB Audio & Video designed a regiment of two-inch absorption panels and installed them along the back wall. They soaked up most of the energy above 1kHz and a good deal below that frequency. The former gymnasium was fast becoming a worthy house of worship.
What the absorption and diffusion had done sonically, the aesthetically well-considered stage did visually. The church independently built risers for the choir and placed a muted, respectable curtain from floor to ceiling behind the stage area. They left the ceiling in its pre-sanctuary, tecktum-paneled state, and, except for 900 acoustical absorbers in the form of church members, left the floor untreated. Years from now, when funds allow, the church plans to build an even larger sanctuary, at which point the gymnasium will return to its roots. The exposed free-throw lines wait for that day.
The physical renovation made a vast improvement, but it could have easily been undone with inappropriate speakers or poor placement. "We needed superb pattern control," Armstrong recalls. "Although we did diffuse the side walls, it was still best to keep as much energy off them as possible. We wanted all of our energy focused on the seats so that we could keep our overall energy level as low as possible. We didn't want things splashing around in that boxy room. The only loudspeaker manufacturer that I know of with true pattern control is Danley. Other boxes will say they're 60 x 40, for instance, but once you get down past 500Hz, everything opens up and you've got no real pattern. With Danley, once you get outside the pattern of the horn, it just drops off, exponentially, regardless of the frequency."
Using Danley loudspeakers, Armstrong designed a system that was simple and elegant. He flew two 50˚ x 50º Danley SH-50 Synergy Horn (Patent Pending) full-range loudspeakers directly above the pulpit. He supplemented them with two 110˚ x 110˚ Danley SH-100 Synergy Horn full-range loudspeakers 35 feet in either direction from the center cluster and angled in at 45 degrees, to ensure that nothing hit the sidewalls. Two more flown SH-100s served as low-energy choir monitors.
But of course, full-range was not enough. When the moment was right and the bass was heavy, the hearts of church members would be moved—and not just figuratively. Armstrong hard packed two Danley TH-115 Trapped Horn (Patent Pending) subwoofers above the main cluster. He notes, "The Danley subwoofers use a proprietary design that generates an amazing amount of clean, thunderous bass from a relatively small cabinet. The absorption treatment had tightened the room up nicely, and the TH-115s provided the system with an equally tight low end."
Armstrong specified new QSC RMX-Series amplifiers to drive all of the house loudspeakers. RMX 4050s powered the SH-50s, RMX 2450s powered the side fills, and RMX 5050s powered the TH-115 subwoofers. He used the church's existing Crown Macrotechs for the choir monitors and for their existing stage wedges. An existing Crown USM810 provided processing, although Armstrong commented that the Danleys required almost no equalizing, and an existing 40-channel Soundcraft Series 2 console fed the whole system.
"It's amazing that we were able to take a gymnasium and turn it into a bona fide sanctuary," Armstrong says. "It's certainly not dry, but we've taken it from seven-and-a-half seconds down to two seconds. The Danleys are a dramatic improvement over their old sanctuary loudspeakers, and the difference is obvious even to church members who have no special interest in audio. Their minister of music, Brian Chrisman, reported that the whole church is ecstatic about the vastly improved intelligibility, and since their style is blended with a heavy lean toward contemporary, they take full advantage of Danley's unique ability to stay clean even at extreme SPLs."