American Idol is getting older and wiser. For Season 4 of Fox's monster hit, some of the "kids" waiting in line to audition may be pushing 30. "We felt the process could withstand widening the age range," says executive producer Ken Warwick, who added four years to the previous upper limit of 24.

After five weeks of audition shows in such cities as San Francisco, New Orleans and St. Louis, there will be three weeks of elimination rounds.

But instead of what we've seen before — 32 finalists competing in four groups of eight — the producers have decided to cull 12 men and 12 women from the hundreds invited to Hollywood. For three weeks running, the women compete against each other one night and the men slug it out the other, with a results show the third night. In the end, the show is left with 12 finalists: six men and six women.

Why? "Last year," Warwick says, "we were a bit embarrassed. We had loads of girls go through [remember the Three Divas?] and not very many boys." This reshuffling gives the show a reason — other than stuffing the schedule with extra "bad audition" episodes — to be on three times a week for at least three weeks. The first live competition will air February 22.

As for the voting process, the show is sticking with its two-hour window, which allows people to call toll-free or pay for text messaging.

This time, four guest judges — LL Cool J, Gene Simmons, Brandy and Kenny Loggins — were invited to join Randy Jackson, Paula Abdul and Simon Cowell in audition cities only; there will be no guest judges on the show. When it comes to musical guests, producers are still salivating at the thought of a Lennon/McCartney night with Sir Paul in person, or snagging Stevie Wonder. "But they've eluded us," Warwick says.

Expect theme nights that revolve around decades: the Motown '60s, the soft-rock '70s, the disco '80s. What you won't see? Vows Warwick, "You are never gonna see rap."