Chris Rock and Metallica at Benarroo Music & Art Festival

Metallica's Lars Ulrich and Kirk Hammett introduced Rock, and the comedian in turn introduced who he called "the baddest ... band in the world." Both acts were unlikely fare for the Bonnaroo Music & Arts Festival, which began in 2002 as primarily a jam band event.

But in recent years, Bonnaroo has broadened itself and brought more diverse fans to its 700-acre countryside site south of Nashville. Among the tens of thousands of festival-goers, Rock, Metallica and many other performers were very conscious of their entry into a tie-dyed world they seldom traffic in.

In a bit in his set about Prozac and other medications, Rock chastised the crowd, who he said was likely on "performance-enhanci ng drugs." "You all should be ashamed of yourselves for taking antidepressants to see a comedian," joked Rock. "I am an antidepressant!" Metallica also touted its cheerfulness.

"Do you feel good?" lead singer James Hetfield asked the crowd. "Metallica is here to make you feel better." Performing on the main stage Friday night, Rock jumped right into his material, much of which he's performed during recent touring. Looking on backstage were many of the other comedians performing at the festival, as well as Jack White, whose band the Raconteurs took the main stage earlier in the day.

Rock worked the giant crowd without missing a beat in his timing, hitting on the election, Anna Nicole Smith and high gas prices despite the war in Iraq, ("If I invade IHOP, pancakes are going to be cheaper in my house," he said).

Metallica had a more difficult time winning over the crowd, which was head-banging but apparently not moshing. Hetfield repeatedly urged the audience to sing along. He asked, "We do have a few Metallica friends here, yes?"

Hetfield occasionally informed the crowd the titles of the songs they were playing and which album they were from. "That was `No Remorse' from `Kill `Em All,'" he said, an annotation that would have normally been completely superfluous for the band.

But Metallica is an exceptionally hard working band — they could be heard practicing backstage in a trailer shortly before their set. Eventually, they won the crowd over with their tenacity, as well as classics like "Sad But True" and "Enter Sandman," the latter of which was accompanied by pyrotechnics.

Usually sold-out with an attendance of 80,000, this year's Bonnaroo hadn't yet reached capacity, but was overrun with tens of thousands of fans who came from far and wide to camp through the weekend. "So is everyone having a nice communal experience?" Vampire Weekend lead singer Ezra Koenig asked the crowd. He later added, with perhaps some sarcasm: "You guys, I'm sure, have a full weekend in store of discovering yourselves and others."

(source: msn.music)