When the band brings the tail end of its Odyssean Madly in Anger With the World tour to Nashville tomorrow, expect treats aplenty for longtime devotees. ''We're pulling out songs that haven't been played in 20 years, some that haven't been played at all,'' bassist Robert Trujillo says, gushing about ''getting the guys to play songs like Dyers Eve or Disposable Heroes, kind of fueling that.'' ''We'll basically learn it on the spot and go out and actually play the darn thing. . . . You'll get this amazing rendition of a particular song that hadn't been played, or you'll get a borderline mess. But that's the fun and the spontaneity of what we're doing now � and the new magic of this band.'' A return to some of the band's more ferocious early material shouldn't surprise, considering the album the band is touring behind. Last year's St. Anger is an under-produced, raucous slab of unrepentant old-school metal, a disc that Trujillo calls ''heavy, raw and in your face'' and the band's label, Elektra, he admits, called ''commercial suicide.'' ''Obviously, the album isn't based on ballads and singles,'' he says, ''and I respect them for that, because Metallica does what Metallica wants to do. They take chances, they always have, and that's why the fans have a love/hate thing but always come back. For me, it was great, because St. Anger is the launch pad for what we're gonna do.'' Producer Bob Rock handled low-end duties on Anger, so the material Metallica is going to do (recording is planned to start in February) will be Trujillo's first recorded input. ''We already have over 50 hours of song ideas recorded,'' he says. ''There's some speed, some of it is kind of raw and funky, most of it has that heavy groove which I think is a stand-out ingredient for Metallica. . . . James is throwin' down some killer riffs . . . and whatever it is man, it's gonna be heavy. We're getting really excited about doing an album as this team.'' Metal's reigning kings weren't exactly been brimming with go-team excitement a year and a half ago when Trujillo joined. Longtime bassist Jason Newsted had walked off, citing personal differences, front man Hetfield emerged from rehab and tensions between him and drummer Lars Ulrich boiled hot enough to drive the band into therapy. That therapy, finding a clear, creative direction and the injection of Trujillo's mellow beach-boy personality proved their saving grace, though. And, they invite fans to witness every step of that breakdown/rebuilding with Metallica: Some Kind Of Monster, a documentary filmed during the making of St. Anger that they'll release on DVD in January. ''It's not just about a band, it's about a relationship,'' Trujillo says. ''People who (hope) to see a concert movie, they're gonna be bummed because that's not what it's about. There's more to this band than what people think � it isn't all about the metallic shield.'' Today's Metallica redresses a lot of what people have thought about the band: The reckless party atmosphere that earned the band the nickname ''Alcoholica'' early on is a return-to-form you certainly won't see on this tour. ''Everybody's pretty healthy these days,'' Trujillo says with a laugh. ''As you get older, you change your lifestyle a bit; we obviously can't be drinking all night and then get up there and try to throw down. . . . We have a chiropractor, believe it or not, who travels with us and whips us back into shape so we can get onstage and hold it down.'' Even with their focus shifted from liquor-pickled bones to properly aligned ones, Trujillo's quick to assure that Metallica still holds it down like few other bands can. ''It's the most physical gig I've ever done,'' he admits.