The 2,500-seat worship sanctuary at Cartersville Church of God, Cartersville, Georgia, offers a new left-center-right (LCR) main sound system designed and installed by dB Acoustics and Sound.

The firm, based in Gainesville, Georgia and led by Mike Hedden, formulated the design to take the place of a proposed new system that utilized dozens of loudspeakers that provided mono audio. "We were asked by the church's technical director what we'd do differently from the original plan if we had the opportunity," notes Hedden.

"Because the church is very heavily involved in drama and music, we proposed a left-center-right design which would greatly improve imaging and fidelity.”

“We built EASE models of the originally proposed mono system as well as our alternate design and the church ended up going with our design,” he continues. “For starters, the mono design placed speakers in areas where there was no structural steel to fly the units and no easy access by either catwalk or lift. Our design took advantage of the front catwalk to fly the speakers and this resulted in a much less obtrusive installation. And as a bonus, we brought the audio part of project in $50,000 under budget."

The loudspeakers comprising the clusters are from Sound Physics Labs. dB installed 10 SPL-td1 speakers and four ServoDrive C-3 Contractor Cubes for front fill in three clusters, flying them about 25-feet apart from the ceiling above the front stage area. While the center cluster consists of four horizontally-flown td1s with two Contractor Cubes below, the left and right clusters consist of three td1s arranged horizontally, with one Contractor Cube below each. For subs, two Belisle Dual 18-inch bass speakers were positioned each side of the stage area.

The church's use of the td1s eliminated the need for delays for balcony fill areas. Hedden said the 60-degrees of vertical pattern control the speakers deliver allows for better coverage than products offering a 40-degree pattern.

In addition to the SPL components, dB utilized a Yamaha DM2000 with additional mic preamps and an O2R96 digital mixing console also with mic preamps; six Crest CA12 amps and two Crest CA9 amps; and Peavey Media Matrix X-Frame 88.

The system was tuned and voiced utilizing SIA SMAART as well as a Gold Line TEF 20. The TEF was used primarily for acoustical measurements, specifically the Polar ETC module. This allows the azimuth and angle of reflections to be seen in a two-dimensional as well as a three-dimensional view. As seen in the example below, it has proven to be invaluable in strategically specifying acoustic treatment.

The arrows show the late arriving energy coming off the back wall of the upper balcony. Notice how the room starts to decay in the first 100 ms and then begins to build up to the noted reflections. After this time frame the room begins to decay as it should. This is a common focusing issue with radius/fan shaped rooms.

In addition, four Sennheiser Evolution Wireless Handheld EW 565-B mics; four EW 512-B Evolution Series 5000 Wireless Lavalier Mic Bodypacks; and two ASP1/NT1 Sennheiser Passive Antenna Splitter Kits keep the sound clean and reliable. "

For more info go to http://www.soundphysics.com