MORRISON, Colorado — Radiohead were so disillusioned after their last North American tour that they wrote two albums' worth of songs about alienation. On the second stop of their summer tour Wednesday at Red Rocks, they held the stage for more than two hours and 22 songs as if to assure fans: Hey, we're OK.

Starting eight months ago with Kid A and continuing with the just-released Amnesiac, Radiohead replaced Thom Yorke's old-fashioned emoting with ambient textures and experimental production. Nearly void of guitars, Radiohead's recent records border on intelligent dance music. Some old-line fans have grumbled that they're void of emotion, too.

At a sold-out Red Rocks, though, the band transformed those anti-rock songs into guitar-driven barnburners. They opened with "The National Anthem," a bass-heavy stomper, and then moved into Amnesiac's "Morning Bell" with Yorke sitting at a keyboard. On record, the former is a paranoid scramble, the latter a claustrophobic lament. But the organic instrumentation in the live show recast them as Bends-era statements: Life is lonely, relationships end, let's get on with it.

The whole show was like that — uplifting despite the bleak lyrics, largely because of the invigorated arrangements. When Radiohead's famed three-guitar attack returned, as it did on "Paranoid Android," Yorke got so into his axework that he tripped over a monitor. During the slow-burning "You and Whose Army?," a buoyant, piano-playing Yorke twice glanced over his shoulder at the crowd, as if to say "How d'ya like that, mates?" Here's how much fun Thom Yorke appeared to be having playing rock and roll again: He cracked up laughing during "Exit Music (For a Film)" and hugged a fan before "I Might Be Wrong."

You knew drummer Phil Selway felt equally giddy when he started snapping crowd pictures. Selway was key in translating for the stage songs that were recorded largely with synthetic beats, humanizing the inhuman.

If anyone was introspective it was guitarist Jonny Greenwood, who spent the night behind a two-tiered baker's rack of gear and stood before about three acres of effects pedals. Greenwood has emerged as the band's star musician, using sequencers and keyboards more often than his guitar, but dutifully delivering the soaring lead on "Airbag."

At the end of a heavy "Everything in Its Right Place," Greenwood and Ed O'Brien remained seated onstage, teasing out a droning guitar and vocal loop while the rest of the band relaxed offstage before the first of two encores. Reaching back to the mid-'90s, they later dusted off "Bones," "Street Spirit" and the show-closing guitar assault "My Iron Lung."

Radiohead used the body of their set to answer fan concerns that, like the Beach Boys' Pet Sounds, their new and fanatically produced albums would be unplayable live. They used their encores to discourage the idea that they've abandoned their traditional rock roots, reasserting themselves as an organic band.