They say you can't go home again. But after nearly a decade of ironic bombast and bloated concept tours, U2 has returned to the rock classicism - and the generous spirit behind it - that made the band great in the first place.


Everything about the new album, ''All That You Can't Leave Behind,'' and the tour, titled ''Elevation,'' is geared toward getting back to the fundamentals of music and of living. The symbolism of playing on a hollow, heart-shaped stage - of filling the empty spirit with life-affirming music - infused the show from beginning to end.


They dispensed with artifice from the moment Bono (who proclaimed that his voice was back, and indeed it was), the Edge, Larry Mullen Jr., and Adam Clayton walked, with no fanfare, into a brightly lit arena and played ''Elevation.'' The production was both minimalist and aggressively egalitarian by arena standards. The spare stage was postcard-size; there were no props, and little high-tech lighting.


The most prominent features of this show were the massive speakers - a testament to U2's renewed focus on the music over the musicians' posturing - and a giant heart-shaped catwalk that brought Bono face-to-face and hand-to-hand, over and over again, with his fans. It was a triumph of intimacy over attitude.


As much as the FleetCenter could, it felt like a nightclub. ''Touch me, touch me, touch me,'' Bono wailed during ''Beautiful Day,'' as he leapt onto the heart's tip for the first time. He lay his body into the crowd during ''Until the End of the World,'' slithered and crawled nearly off the catwalk on ''Mysterious Ways,'' kissed and dueled and rested his body against the inimitable Edge - with whom Bono shared a powerful musical and physical chemistry. It would seem they've missed the closeness as much as the fans have during a decade of sometimes brilliant, but increasingly alienating, musical personas.


But Wednesday night it was all about the music and the love, which for the most part felt inextricably bound.


The sold-out crowd at the FleetCenter shared it with 45 million television viewers during a shamanic ''Where the Streets Have No Name'' and the hauntingly melodic ''Pride (In the Name of Love),'' which were broadcast live during halftime of the NBA finals game in Los Angeles.


But U2 knew exactly where they were. Bono name-checked Harvard Square, the Big Dig, and the Irish on Summer Street in a riff on a stripped, pummeling version of ''Desire.'' And one lucky Boston fan was pulled onstage, handed one of the Edge's guitars, and accompanied Bono on Curtis Mayfield's ''People Get Ready,'' the B-side he'd requested.


In a poignant moment, Bono dedicated ''In a Little While'' to the late Joey Ramone, noting that ''it was the last song he heard in his life here.''


It's sentiments like those that freed U2 from the ironic distance they once brought to their concerts. Intensity and passion - that much sweeter for being lost and found - carried them through Wednesday night.


PJ Harvey opened with a set of dense, visceral rock. Her uncharacteristic evening dress and elegant makeup was a jarring juxtaposition to the darkly roiling sonic and emotional landscapes she cobbled.