Ferocious hippie that he (still) is, Neil Young spent his first hour on stage at the Tower Theater on Sunday singing acoustic songs of fragile beauty that sought spiritual calm and longed for lost innocence. Then, for the next hour and a half, he stood up, plugged in, and tore it all to shreds.

At 62, Young remains a legendary iconoclast, a restless tinkerer who's literally always in motion, even when sitting down. His loose-limbed swaying knocked over one of five guitars arranged on a stage that resembled your grandmother's attic, during a terrific "Cowgirl in the Sand" that closed the first half of the highly entertaining evening.

"It just wants to jam," he said, unflummoxed as always. When he resumed the song, he strummed the guitar's neck to grant its wish.

For decades, Young has been talking about putting out an epic multi-disc compendium of his unreleased material. Who knows when that'll happen, but the Canadian child of the '60s has clearly been perusing his back pages.

His uneven new album, Chrome Dreams II, from which he did four songs - including a 19-minute, endurance-test fuzz-rock version of "No Hidden Path" that didn't quite justify its length - is a sequel to a 1970s LP that never came out. And the guiding principle of the tour, which was scheduled to bring him back for another sold-out Tower show last night, was to mix trademark tracks like "After the Gold Rush" (performed on piano) and "Like a Hurricane" (a hellacious encore) with forgotten rarities.

On the opening "From Hank to Hendrix," he laid out the pitfalls of his artistic strategy: "Sometimes it's distorted, not clear to you / Sometimes the beauty of love comes ringin' through." He then pulled out oddities like "Campaigner" - revered by Neil know-it-alls for its "even Richard Nixon has got soul" hook line - and "Sad Movies," which before this tour, had not been performed live since 1976.

The acoustic portion of the show was prefaced by an announcement that prohibited cell phone use of any kind, the calling out of song requests, or the consumption of any food or beverages in the theater during the acoustic set, so Young could "concentrate on the music." That was a hard edict to swallow for the rowdy, multigenerational crowd, but it paid off with a committed, engaged performance, and a cheerful and thankful Young.

"I find myself thinking of W.C. Fields for some reason," he said, thinking, presumably, of the comic's proposed epitaph, "I would rather be living in Philadelphia." Added Young, "He was a funny guy."

When he went electric, Young was backed by bass player Rick Rosas, multi-instrumentalist Ben Keith, and Crazy Horse drummer Ralph Molina, and on backup vocals, Anthony Crawford and Young's wife, Pegi, who opened the show with a pleasant set of laid-back country-rock.

The second set delivered no shortage of theatrical weirdness. Before each song, the Panama hat-wearing tour manager Eric Johnson set a work-in-progress painting on an easel, illustrating the song's title, be it a powerfully stomping "The Loner" or gloriously self-pitying "Oh, Lonesome Me." A disco ball hung beneath a paint-smeared grand piano, and a wooden Indian observed the performance, which was being filmed by Jonathan Demme, who directed the 2006 Young concert film Heart of Gold.

Through it all, Young's keening, high-pitched vocals and convulsive guitar attack were every bit as feral and impassioned as his loyal fans, who plunked down as much as $150 for tickets, have come to count on. After more than four decades of music-making, Young's risk-taking studio albums are understandably inconsistent. But on stage, he never disappoints.