The recent Nashville CMA Fest marked its milestone 50th anniversary with more than 300 artists and acts who attracted an estimated 90,000 fans on each of its four days, with the main stage in Nissan Stadium once again equipped with a large-scale sound reinforcement system headed L-Acoustics K Series loudspeakers and supporting components supplied by Sound Image Nashville.
The main stage hosted performances from a “who’s who” lineup that included Alabama, Ashley McBryde, Dan + Shay, Dierks Bentley, Elle King, Jason Aldean, Lainey Wilson, Luke Bryan, Luke Combs, Miranda Lambert, Tanya Tucker, Tim McGraw, and more. The sound had to meet some very high standards, says Sound Image system engineer Bill Chase, designer for the project.
“It was a festival of primarily A-level artists who all have their very specific demands for audio,” he notes. “It’s also a high-profile event with very high expectations. Literally, everybody in the industry comes, and the festival is televised. We’ve found that no one is disappointed when they discover they’re going to be mixing on an L-Acoustics system.”
Chase worked on the project with Sound Image crew chief Philip Piercy, previous system engineer Roz Jones, and a team from L-Acoustics that included applications engineer Vic Wagner, touring engineer liaison David Brooks, and applications consultant Erika West. Although Nissan Stadium, home to the NFL Tennessee Titans, has fairly predictable acoustics, it does possess some unique features that can affect sonic response, including a very large video wall at one end.
Chase explains, “If you were to deploy the PA as most would, which is to use the mains to cover as much as possible, you’d end up with a lot of slap-back. So, we avoided that by tightly covering the field and lower bowl with our main hangs and then using the outfills and delays to address the rest. Some of the arrays were asked to cover well beyond what one might typically think would be possible, but Soundvision showed us that the system we designed would work — and it did. There was impact from the kick drum and full frequency response everywhere — even in the farthest reaches—and no sound quality compromises whatsoever to any seat in the house.”
Designed in Soundvision, the system utilized 52 K1 and 68 K2 line source array enclosures, with left and right main hangs sporting six K1-SB over 14 K1 and four K2 downs while the outfill arrays counted 12 K1 over 12 K2. Low-frequency coverage was reinforced by 36 ground-based KS28 subwoofers stacked three-high in a cardioid configuration as well as 10 K1-SB per side flown behind the mains to aid in even coverage and rearward rejection.
In addition, eight additional K2 were hung per side as far outfills for the upper bowl seats, and ten more K2 per side were flown out in the gridiron seating for delay. A dozen Kara II used as various fills rounded out the enclosure tally, while 90 LA12X amplified controllers powered the loudspeakers, which were processed via the L-Acoustics P1 Milan AVB processor and M1 measurement tool.
In particular, Chase cites the benefits of the Autoclimate function, which allows for the simultaneous adjustment of all air-compensation filters based on measured temperature and humidity conditions, accounting for the specific shooting distance of each zoning group. “It’s pretty amazing the amount of distance we can cover with L-Acoustics, but it’s equally amazing how it can adapt to changing weather conditions using Autoclimate and Autofilter,” he says, the latter processor further assisting with uniformity and flatness of the high-frequency response, determining and applying linear-phased FIR filters to zoning groups within an array.
“For instance, when these crews come in the morning for sound checks, it’s hot and dry, but at night, it cools down and becomes more humid. Yet we can keep the PA sounding consistent throughout the whole venue the entire day thanks to tools like these that make a system engineer’s job easy, especially with the PA as large as this. With an event as big as CMA Fest, L-Acoustics is as good as it gets.”
