SALT LAKE CITY, UT — Salt Lake City’s LDS Conference Center has taken a recent installation of an L-ACOUSTICS dV-DOSC loudspeaker system. First opened in the spring of 2000, the 1.4 million-square-foot Conference Center is home to the semi-annual LDS General Conference, which packs in a full house and is broadcast worldwide out to 12 million people. Each Sunday the Center hosts a performance by the Mormon Tabernacle Choir — a weekly rite now in its 77th year. The Center is also available as a rental venue for \ concerts, ceremonies and meetings. According to sound engineer Trent Walker, “We get quite the gamut of performers who come through this room. In addition to LDS events there are approximately 25 other shows per year, including the National Rotary and World Barbershop conventions, concerts such as a recent performance by The Oak Ridge Boys with the Mormon Tabernacle Choir to benefit Feed the Children, and a variety of guest soloists who perform with the choir every week.”
With such events being held on a regular basis, it is crucial that not only are the choir and orchestra heard in high enough fidelity, but also that the spoken word be heard clearly and evenly at every seat. The sound system that was originally installed in 2000 was never adequate for the room, and Salt Lake City-based Poll Sound, led by general manager and lead sound system designer Deward Timothy, was tasked with creating a new system that would do the room justice.
The facility is large enough to hold a Boeing 747 and has a rounded back wall, so making adjustments to the system to minimize reflections was no easy feat. The left and right PA speaker positions are 120 feet apart — the width of the stage — making it difficult to create an image. Another issue was the existing structure. Timothy explains, “When the building was originally designed, they didn’t want the arrays showing, so they created cavities for them to go into. These cavities would require some pretty serious modifications to fit the new equipment, including a fair amount of new steel for support, as well as modifications to the grilles so they could be as far forward as possible.”
The first step in the process was to make a computer model of the room. L-ACOUSTICS was able to take Poll Sound’s existing EASE model and convert it. L-ACOUSTICS vice president of sales and marketing Paul Freudenberg explains the next steps: “We modeled a couple of different loudspeaker approaches and evaluated them for performance in terms of coverage and sound pressure level. As part of this process, we’re also able to find out how physically large a sound system and speaker array will be, as well as the weights — statistics that will be helpful for engineering purposes. For instance, if we find that a system will be too heavy for the rigging point, we are able to be proactive and change our initial approach or consult with engineering for an alternative.”
After running models, Poll Sound opted to go with the dV-DOSC system, having previously installed a dV-DOSC rig in the 905-seat theatre in the same building.
Walker stated, “The dV-DOSC line array solved a lot of problems for us in a room this size. The natural sound it has provided has really been the answer we were looking for.”
The front-of-house system is set up to be an LCR system with 18 dV-DOSC cabinets flown per side and six dV-SUBs for extended low-frequency reinforcement. The foldback system for the choir and orchestra runs 16 discreet mixes, and monitors deployed are a combination of L-ACOUSTICS MTD112b and MTD108a enclosures.
When it was time for tuning, Timothy said, “We loaded the L-ACOUSTICS preset file for our processor and, to be perfectly frank, we didn’t change it in the least. We did some minor tuning after the fact, but their factory preset was almost right on.” Freudenberg elaborates, “As part of our standard process, we provide a set of factory produced presets for DSP processing — crossover points, delay points, EQ points and so on.”
The first show in the main hall with the new dV-DOSC system was the American Forces Radio and Television Service’s Christmas broadcast to the troops, which featured contemporary Christian artist Sandi Patti performing with the Mormon Tabernacle Choir and Orchestra. Trent Walker noticed, “The goal was to ensure that we had coverage and that what is heard is the purity of the music, not the speakers. We are now getting a stereo image in a large portion of the room, and that has made a huge difference for our audience.”
For more information, visit www.pollsound.com or www.l-acoustics.com.
