L.A. Reid L.A. Reid

It's time for The X Factor to get down to business.

Beginning with Wednesday's episode, Fox's singing competition moved to the second phase of its sophomore season: boot camp, where the 120 or so contestants who made it through the first round of auditions will be whittled down to just 24 over the course of a week. According to judge L.A. Reid, boot camp really ups the ante for the hopefuls.

"On the first audition, God knows how long they've rehearsed," Reid explained on a recent conference call with reporters. "We get to boot camp, they don't have any time to prepare. So, now it's like we separate the boys from the men. We see what you're really made of. That's exciting to me."

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Still, Reid insists that the intensified challenges are nothing compared to what the performers will go through if they truly want to become superstars like Britney Spears and Demi Lovato. "They didn't become a success because they were slackers," Reid said of his fellow judges. "Both of them worked really, really hard coming up the ranks. ... They put in the work. So I think that the kids that we have in boot camp, we're putting them through drills that are a fraction of the drills that Britney Spears has gone through. And I'm saying that knowing that boot camp is tough. We're putting these guys through rigorous, rigorous tasks to really see if they're qualified to go through to the next round."

The contestants aren't the only ones facing higher stakes, Reid said. In boot camp, he and the rest of the judges — Simon Cowell, Spears and Lovato — will start to offer more feedback on the performances, as they prepare to move into their mentorship roles later in the season. "It gives us a different kind of a momentum, because that's when we the judges are actually participating at some level," he said. "It's a different stage for us, simply because we're not just sitting there in judgment, but we're actually participating."

But if Reid sees any frontrunners going in, he's keeping them to himself. "I have many, many favorites. Too many to name," he said. "The competition in boot camp is going to be so stiff. I can't predict the outcome because there's so much good talent this year."

The X Factor's boot camp phase continues Thursday at 8/7c on Fox.