Nickel Creek / Nov. 19, 2005 / Tampa, Fla. (Tampa Theatre)

Is Nickel Creek a bluegrass band, or not? The trio of SoCal twentysomethings, who have played together since they were preteens in San Diego, long ago apparently decided not to decide. In terms of art

Is Nickel Creek a bluegrass band, or not? The trio of SoCal twentysomethings, who have played together since they were preteens in San Diego, long ago apparently decided not to decide.

In terms of artistic payoff, that was the best decision ever made by mandolin player Chris Thile, fiddler Sara Watkins and her older brother Sean, as the three, plus bassist Mark Schatz, demonstrated yet again with a rangy, barn-burning show at historic movie palace Tampa Theatre. They used bluegrass instruments to play original songs and a few covers in a manner that's distinctively their own, notwithstanding critics' comparisons to the likes of Radiohead and Coldplay.

"Why Should the Fire Die?," Nickel Creek's recently released third album for Sugar Hill, was the source of much of the concert material, including spooky show and album opener "When in Rome," which kicked in with a full band attack before dropping down to a whisper for Thile to ask, "Where can a dead man go?"

Also hailing from the new disc were "Best of Luck," with its cascading harmonies; the waltzing "Jealous of the Moon," co-written with the Jayhawks' Gary Louris; the old-timey "Anthony," which Sara Watkins began alone, on vocals and ukulele, as all crowded around a single mic; "Helena"; "Somebody More Like You"; and the stomping instrumental "Stumptown."

Nickel Creek, as is its habit, injected the show with fresh spins on covers, including a giddy take on Randy Newman's "Short People," a swaggering run through the Beatles' "Cry Baby Cry," and, on the encore, the Band's "Up On Cripple Creek" and vintage bluegrass favorite "Whiskey Before Breakfast."

Longtime fans of the band weren't forgotten. The set list also featured pieces from earlier Nickel Creek albums, including the mellow, loping "When You Come Back Down"; "Sabra Girl"; the pretty "Reasons Why"; and the much-requested "The Lighthouse's Tale," which built into a frenzied fury.

Journeyman mandolin master Mike Marshall, who grew up in Central Florida, joined the band for "Whiskey," and faced off with Thile for an extremely exuberant, comical take on Marshall's "Gator Strut." The two, who teamed for 2003's "Into the Cauldron" CD, are pairing for a string of duo performances which resume in January in Marshall's regular stomping ground of northern California; they sound as if they were born to a long, productive musical partnership.

Thile, the Watkins siblings, Schatz and Marshall live to play music. Why else would they chase their performance at a sold-out venue with an impromptu unplugged performance on the sidewalk, adjacent to the venue's exit?

The five, plus 15-year-old Florida mandolin ace Josh Pinkham, treated 100 or so fans to an extended post-show picking session, ala the kind of late-night jams that typically pop up at bluegrass festivals. The set included "Sweet Georgia Brown," "Cocaine's Gonna Kill My Honey Dead," "Lady Be Good," "You're Gonna Make Me Lonesome When You Go" and "Take Me Back to Tulsa."