The Who, having often faltered in the recording studio, has always towered on the concert stage. It may be that the group's backlog of classic rock 'n' roll songs precludes much risk-taking in performance. But at the Capital Centre last night, where the Who kicked off a farewell-American tour, the band performed with the vivid urgency of beginners. In the process of openly celebrating their history -- and putting a cap on it -- the Who peppered their enveloping wall of sound with sudden slashes of chaotic energy and intense emotion that enhanced (and occasionally offset) the familiarity of the songs.

Walking on to a chorus of "Who's," the band kicked off, as it has for years, with "Substitute" and "Can't Explain," both fundamental rockers that quickly established the evening's parameters: The immensely charismatic Pete Townshend would still crash out his windmill-powered chords and accent them with effusive scissor kicks; Roger Daltrey's vocals would be as effortlessly gutty as his lariat-mike patterns; John Entwistle would stand still and pump out his sturdy bass throbs, while Kenney Jones kept a hard, tight beat on drums, often sliding into a martial insistence. It was a familiar scenario, fully energized, the hard rock dynamics exorcised by Townshend's pure pop philosophy.

Although it would have been easy to rest on laurels, the Who performed four songs from their new album: "It's Hard," given a harder, compelling edge; the mellow-to-madness "A Man Is a Man," and the percussively bassed and thoroughly delightful "Eminence Front" and "Cry If You Want."

While Daltrey carried the vocal load, Entwistle and Townshend were almost as strong in their occasional forays to the mike -- the bassist given to a lyrical, almost R&B fervor, the guitarist anguished and emotionally revealed. No matter who sang, they were buffeted by archetypal whiplash chords and powerhouse rhythms that confirmed the Who as one of the world's finest concert attractions.

There were sluggish moments -- a jolly but sloppy encore of roots oldies as well as a few Who tunes that seemed either unrealized or curiously dated. But the pluses dominated, from Townshend's tinsel guitar solos to chiming harmonies to the Tim Gorman's simmering synthesizer setups for "Baba O'Riley" and "Won't Get Fooled Again" to a synoptic overview of "Tommy" with shafting power chords and an anthemic chorus that was as visceral last night as when it was first heard. Could it really be 13 years ago?

In saying goodbye from a position of strength, the Who has also managed to put the heart back in the beat so necessary for primal rock energy. Listening to them, we get the music -- the tradition as well as the promise -- in one climactic whole that guarantees rock a long life even after they are gone.

The Who performs again tonight.