Stagecoach Country Music Festival

Country music fans dash across the Empire Polo Club fields to reserve the best viewing spots as the gates open on the opening day of the Stagecoach Country Music Festival. (Allen J. Schaben / Los Angeles Times / April 26, 2014)

The most prominent acts at Indio's Stagecoach Country Music Festival last year represented a diverse mix of men and women singing about family, tradition and "picture-perfect memories scattered all around the floor."

Twelve months later, the headliners of the annual festival's 2014 edition, which kicked off Friday, are best known for hits about partying, partying — and then partying some more.

"The energy — it's gonna be high," Eric Church promised of his Friday-night Stagecoach performance. "But with us it's always high."

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Church and fellow headliners Jason Aldean (Saturday) and Luke Bryan (Sunday) are three of the biggest stars in Nashville, each a testosterone-soaked embodiment of the genre's latest development, often referred to as "bro country."

So named for its appeal among rowdy young men, the up-tempo style uses muscular rock guitars to put across songs celebrating the joys of beer, women in bikinis and unfettered access to various bodies of water. It's so saturated country radio at the moment that even Brad Paisley, that established A-lister, was moved to embrace some of its conventions — or is he sending them up? — in his latest single, "River Bank."

The bro-country vibe at Stagecoach "is only following where the market is," said Jay Williams, a William Morris Endeavor booking agent whose clients include Bryan and Church.

The biggest-selling country album of 2013 was Bryan's "Crash My Party," followed closely by "Here's to the Good Times" by Florida Georgia Line, the rambunctious Southern duo that's also on the bill at Stagecoach.

This week Bryan is on top of Billboard's Hot Country Songs chart with "Play It Again," in which he finds a woman "sitting all alone over on the tailgate" and tries to figure out a way to "pour a little sugar in her Dixie cup." And right behind him? Florida Georgia Line with "This Is How We Roll" and yet another Stagecoach act, Brantley Gilbert, with "Bottoms Up."

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Michael Levine, station manager at L.A.'s Go Country 105 FM, said the festival's lineup is in keeping with an overall trend in the format.

"Our younger demographic is growing exponentially," he said, adding that the station airs a Friday-night show in which popular country songs are remixed with booming club beats.

"We haven't seen any complaints from listeners," he said.

Country's move toward youthful exuberance — after years in which the music's presumed demographic, according to Williams, was "30- to 40-year-old housewives" — mirrors a similar trend in pop.

The biggest draws this month at Coachella, which like Stagecoach takes place on the sprawling grounds of Indio's Empire Polo Club, were acts such as Calvin Harris, the dance-music producer with a deep bag of throbbing electronic jams, and Pharrell Williams, whose performance of his No. 1 hit "Happy" set an enormous field full of people into motion.

Now Stagecoach, with its robust alcohol sales and its own array of half-dressed twentysomethings, appears to be closing the gap between it and the festival sometimes referred to as Bro-chella.

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"Our research shows that fans of classic rock and current rock also listen to country," said Sarah Trahern, chief executive of the Country Music Assn., a Nashville trade group. "We're in a business where people no longer just listen to one thing or another."

Stagecoach's alignment with bro-country stars comes in contrast with previous lineups that were more varied in subject matter, gender and race.

Last year, for instance, the three-day event — presented since 2007 by Los Angeles-based Goldenvoice as a country cousin to its Coachella Valley Music and Arts Festival — featured Hank Williams Jr., Darius Rucker and Lady Antebellum, whose genteel "Need You Now," about those picture-perfect memories, crossed over to adult contemporary radio and was covered on TV's "Glee."