The Followill family band embark on what could be a career-defining album cycle

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As another oppressive Tennessee summer begins to give way to fall, Kings of Leon are in the early stages of turning up their own heat as they shuffle about the comfortable confines of their studio, checking smartphones, twiddling knobs, listening to rehearsal playbacks.

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Dubbed Neon Leon, the studio is a gray, nondescript building located next to a construction equipment business in a semi-sketchy area just south of downtown Nashville. Surely by design, passers-by would have no inkling of what goes on inside these tastefully decorated walls, where in the previous months the band labored on its own construction project. That job is done: Mechanical Bull, its sixth album on RCA, bows Sept. 24.

The stakes are higher than usual, a fact not lost on brothers Caleb, Nathan and Jared Followill and their cousin Matthew Followill. That's particularly true in the United States, where the band's 2011 tour, already plagued by injury and a notorious pigeon-shit incident, ended badly, to put it mildly. A ragged July show in Dallas was shut down when singer Caleb left the stage vowing to vomit, drink a beer and come back out to play three more songs. He did not return.

The remaining U.S. dates were canceled, and band member tweets alternated between apologies and hints of conflicts. The media had a field day, but the group did honor remaining commitments for the year in Canada, South Africa and Australia, a move reported with less fervor. Instead, ominous talk of a hiatus followed, and the future of Kings of Leon seemed to hang in the balance.

Caleb sighs-but doesn't bristle-when the topic is broached. "I don't know. I just had a bad day, I guess," he says with only a hint of a smile. "We'd been playing outdoor venues that were 105 degrees. We were exhausted, my voice was nonexistent. I was doing everything I could to get by."

For the first time since the group distinguished itself as a globally significant rock band capable of crossing over mega-hits and moving millions of albums, Kings of Leon got smacked around a bit. The rock press had long shown the group love, and the celebrity weeklies took note when Caleb began dating (and eventually married) model Lily Aldridge. Perhaps the turn of the tide was inevitable. "It was just our time to step away for a second," Caleb says. "We had oversaturated the market with Kings of Leon for so long that it was starting to take a toll on us."

As it turned out, the singer did have serious vocal issues, according to Ken Levitan, who manages the band with Andy Mendelsohn at Vector Management. "The reality is Caleb was having real problems with his throat," Levitan says. "Was he drinking a bit? Yeah. He was trying to get through the shows. That's partially why he was drinking. But [the tour cancellation] was really a blessing in disguise, because that's how we found out about the issues with his throat. He couldn't talk for two weeks, and the doctor said, 'You're not allowed to sing.' That's the story that didn't get out there."

As it turns out, the band only took a few months off before hunkering down on the songs that became Mechanical Bull. But that work was out of the public eye. "It amazed me how, taking even that small of a break, people were already writing us off," says drummer Nathan, the band's eldest member at 35. "I was getting condolence texts from friends: 'I'm sorry you broke up, man. Keep your head up, it will all work out.' I was laughing so hard, because none of us ever thought it was over."

The band members didn't help matters with their own tweets after the Dallas incident ("I know you guys aren't stupid. I can't lie. There are problems in our band bigger than not drinking enough Gatorade," Jared wrote), and it's clear even now there was tension. "We had a little spat," guitarist Matthew says, "but we were talking a couple days later. We fight. That's normal."

"Brothers fight. You're going to get that," says Levitan, who has worked with the Followills since they were teenagers. "Sometimes the media can run with it, people make a lot of assumptions, and it becomes like a game of telephone."

Beyond illuminating Caleb's now-resolved throat problem, the Dallas meltdown, and the way it landed, served one other purpose: It "showed us how quickly people can write you off," Nathan says. And that "cleared our heads enough to make us appreciate what we get to do."

Mechanical Bull is the work of a clear-headed, focused band. Nathan calls it an "unofficial greatest hits" for the way it melds the best elements from a decade of evolution. It's also an assessment of sorts. "If we hadn't taken that break, it would have been a forced album, something that we just put out there," Caleb says. "Because, like I say, we were exhausted. We were spent."

It was a full decade of relentless album/tour/album/tour cycles that took Kings of Leon from youth to young manhood, as the title of their first record puts it. But, as adults, couldn't they say no when the workload became too heavy? "Things are done so far in advance," Nathan says. "I could feel fine right now, and they've already got shows planned into the end of next year. So you're saying 'yes' to all this stuff, but then six months down the road, when you are playing Chicago for a second time, you're like, 'How in the hell does this happen? We're not machines. They can't just keep putting this on us. We didn't sign off on that.' And they will be like, 'Actually, remember that meeting we had two-and-a-half years ago and we mentioned San Francisco?'"

"After the fifth bottle of wine," Caleb interjects. "You can always tell when they're going to unload stuff on you when they order a nice bottle of wine at dinner. It's like, 'Oooo-K, here we go.'"

The four Followills are now husbands and some are fathers, and the maturity that comes with that will likely be a difference-maker this time around. "In the early days, it was a pissing contest between bands to see who could go out and get the craziest," Caleb says. "Now we're a little more fortunate, we travel a little more comfortably. When we play a show, most of the time we get on an airplane and go to whatever town we're hubbing out of, and we're up at 6:30 in the morning with our kid. So you pick and choose when you're going to let your hair down."