A musical institution for 50 years, the New Orleans Jazz & Heritage Festival takes over the city’s fairgrounds for two consecutive four-day weekends every spring to present dozens of acts on 17 stages and tents simultaneously, making for a considerable live audio challenge.

New Orleans, LA—John Koehler is sitting at a laptop in a production trailer on the New Orleans Fairgrounds, watching an RTA audio readout. This is about as much rest as Koehler—who goes by the nickname “Klondike,” the name of his company, or “Klon” to his friends—gets in a typical day at the annual New Orleans Jazz & Heritage Festival. Before long, the meter spikes and then hovers in the red, and Koehler reaches for the radio clipped to his T-shirt.

“Big Freedia just hit 110 at front of house, you wanna stop over there?” he radios to Deshaun Washington, one of the assistants on site.

He’s talking about the Congo Square Stage, the third largest of 17 stages and tents at the 50th Jazz Fest, which covers every patch of green space and fills the grandstand on the nearly 200-year-old tract in the heart of the city.

“That particular stage is sort of the most rambunctious on the site,” says Koehler. “It’s a lot of low end, which is required for that music—rap, reggae and some R&B. Even though there’s a pretty serious complement of directional subwoofers to keep the low end from going places other than straight ahead, propagation of the sides and rear becomes a problem when they exceed their SPL limit … which is really our primary concern in terms of sound field containment.”

At the Jazz & Heritage Stage were (l-r): Jeffrey Gex, John Koehler, and Brian Hrabar, owner of Propaganda Group

At the Jazz & Heritage Stage were (l-r): Jeffrey Gex, John Koehler, and Brian Hrabar, owner of Propaganda Group

For two back-to-back, four-day weekends every spring, there is no greater collection of eclectic artists and musicians than Jazz Fest. Headliners like Van Morrison, Diana Ross, Katy Perry and Jimmy Buffett share stages with a fleet of pop, jazz, blues and rock artists, alternating slots from 11 a.m. to 7 p.m., when the crowd—which can swell to nearly 100,000 on a given day—disperses to the French Quarter and other parts of the city.

Jumping at Jazz Fest's Jazz & Heritage Stage, by Jim Beaugez, May 20, 2019

For 42 of those 50 years, Koehler has been involved in producing the collection of stages and performers at Jazz Fest. He’s seen it grow from merely covering the racetrack infield to its current size, and has helped the audio component evolve from towers of point-source loudspeaker systems to the line arrays that hang today. Those advancements have enabled them to fit so many performance areas here, an arrangement akin to piecing together a massive jigsaw puzzle.

“My success is directly due to the evolution of the line array,” Koehler readily admits. The sprawling Acura Stage is Exhibit A. As host to the festival’s largest crowds and biggest draws, accuracy in system deployment is the biggest challenge and the most important objective. The lawn spreads out from the massive stage in an asymmetrical pattern, with pockets on either side, a long throw covered by fills, and stands placed around the perimeter. At the rear of the field, the Congo Square Stage competes for audience and air space, pitting artists like Dave Matthews Band against Pitbull.

“Strategically, Dave Matthews has two hours,” says Koehler, “but there’s a significant gap in here to allow their sound to sort of come into its own and hopefully be somewhat well contained by the size of that audience.”

The Dave Matthews Band graced the Acura Stage at Jazz Fest this year, performing through Clair Global’s proprietary Cohesion line array system.

The Dave Matthews Band graced the Acura Stage at Jazz Fest this year, performing through Clair Global’s proprietary Cohesion line array system.

To make everything work, Jim Bowersox, head of speaker development at Clair Global, worked with Koehler and others for months to design the Acura Stage system in a way that balances performance with maintaining good relations with neighboring stages and audiences.

Live Sound Showcase, Mixing Jack White at Jazz Fest, by Jim Beaugez, Oct. 29, 2018

“We may have a pop or heavy rock act playing at the same time as a quieter jazz performance in the tent immediately behind the stage,” says Bowersox. “The use of steered, cardioid sub arrays helps to mitigate excessive low frequency behind and to the sides of the Acura Stage. The speaker hangs are also surrounded by acoustic blanket materials to help improve rear rejection characteristics when the scrim in front of the main hangs becomes wet and excessive high frequency energy gets reflected rearward.”

The hulking system centers on 16 Clair Global Cohesion CO-12 arrays per side, made up of a dozen 80-degree boxes and four 120-degree boxes each. A total of nine CP-218 subs drive the low end in a steered, cardioid configuration on each side as well. A dozen CO-10s, four CP-6 front fills and three delay hangs of eight CO-10s each cover the outlying areas. In total, 30 Lab.gruppen PLM20K44 amplifiers power the rig.

“Clair is a clear choice for all national acts because so many already tour with Clair,” says Koehler, “and if they come in with tour packs, they can easily interface to the Clair stuff because it’s already dialed in.

“The nice thing is the boxes sound the same whether they’re this big or this big,” he adds. “They’re all voiced in a very uniform way, so a global EQ, should that ever be applied from one point upstream, makes similar changes in the intelligibility or sound quality, the timbre, of every enclosure.”

Weatherproofing in the humid Southern Louisiana spring is a significant consideration. Rain delays are routine, and sound companies have to prepare for storms that blow in from the Gulf of Mexico with lightning, whipping winds and heavy downpours. “The system needs to be operational through any weather condition, so waterproofing and thermal performance are of high importance,” explains Bowersox.

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While he can’t control the weather, Koehler can make sure the stages are prepared for whatever season shows up. Ultimately, he is responsible for mitigating the impact of weather on Jazz Fest performances. “I monitor the weather pretty closely because sound is at the mercy of air. Quite frankly, moisture, wind direction [and] temperature all affect how well we propagate and how well the waves stay where they belong.”

It’s a similar story for the Gentilly Stage, Fais Do-Do Stage and every tent on the grounds. At the end of the day, Koehler hopes his work helps festivalgoers relax and discover: “Out here in the field, it can be just a big gumbo of sound, and my goal is to sort of allow the sound to spread where anyone who isn’t committed to a stage can hear it, but as soon as they’re within an audience area, have that sound be attenuated so they can concentrate on the sound that’s in front of them.”

Clair Global • www.clairglobal.com