If the Rolling Stones symbolize the bad-boy aspects of rock 'n' roll, England's Who always stood for commitment, intelligence, responsiblity, ppositive action. The band came up with memorable anthems like "Won't Get Fooled Again," and intelligent rock operas like "Tommy" and Quadrophenia," delivered with inestimable energy.

And Pete Townshend, the band's guitarist, songwriter and spiritual generator, emerged as a conscientious, articulate spokesman for the heart of rock. He defined it mostly by playing it, but sometimes set words outside meter as well: Five years ago, he wrote in Rolling Stone magazine, "if it screams for truth rather than help; if it commits itself with a courage it can't be sure it really has; if it stands up and admits that something is wrong but doesn't insist on blood . . . then it's rock and roll."

Townshend sits in his hotel room, the calm center before the storm of performance. He looks remarkably fit, remarkably young for a man who has been sitting on the razor-edge of rock 'n' roll for 20 years. His pale blue eyes are as clear and direct as his thoughts these days, but a year ago, Townshend almost sank under the myriad weights of alcoholism, drug addiction and family troubles; his face, half-careworn, half-shell-shocked, still shows the strain, but the intense eyes speak of survival and renewal.

Those dazed days are over, buried but not forgotten. There is new-yet-final business to attend to: the Who is calling it quits while it's still on top. Such a departure is a step few bands have survived long enough to take willingly, but Townshend seems intent on ending the Who story with an exclamation mark, not a question mark. "I feel like we're climbing a mountain instead of treading water," he says. "I feel a great sense of . . . relief."

"The way I see it, we'll finish this tour and do a tour of Europe and Britain, make another record and then disband. Basically, I see it as the end of my performing career, but I'm looking forward to seeing what I can do next. It's an aggresive winding up of a period of activity, an aggressive attempt to exhaust our resources. I really want to wring us out dry, and know that we've got everything out of us that is possible."

At Tuesday's rehearsal, the Who played to an almost-empty Capital Centre. As Townshend's windmill guitar strokes created thunder swirls, Kenney Jones' martial drums advanced a brutal melody, and John Entwistle's gut-bucket bass lines underscored everything with finality, while Tim Gorman's keyboard set-up sat mostly hidden and subtly heard behind a bank of speakers. Vocalist Roger Daltrey, looking like a Marine aerobics instructor, restlessly paced the cluttered stage, waiting for a lull in the sound storm to get a few words in.

A moment before, as part of a soundcheck for the first leg of the Who's long goodbye to America, it had been pure, loud cacophony, each musician playing a disparate rhythm, a personal melodic line. And then a word was passed, the disjoints became joined, the power surged from a single source; at the end, soundmen, photographers, publicists and security guards -- all generally jaded voyeurs within the rock business -- broke into spontaneous applause.

The Who returned last night (and will play again tonight) to a full house, but that transcendant moment, that volatile bridge between cacophony and undiluted energy, is a compelling metaphor for the band's personal history and its place in rock history. Having reached a kind of adulthood after 18 years of restless adolescent energy, the Who, with the Rolling Stones, is the of the last great electric beasts, the rock dinosaurs who lumbered in as part of the British invasion an innocent age ago.

Speaking of innocence, Townshend now points out that the two major Who anthems are not what they've always been perceived as. " 'My Generation' is not really about youth, but about class. I was living in Belgravia [in London] at the time, in the embassy district, and I used to look out at all these titled people in their Rolls Royces . . . and I used to walk into the same shops they did and they'd sneer at me. It wasn't so much that they were old, 'cause a lot of them weren't, but they were of a different class and I hated that and I hated them." (The song, despite its classic status, won't be done on this farewell tour: "We dropped it because Roger keeps laughing, which I find embarrassing!")

" 'Won't Get Fooled Again' is really different from what it's taken to be," Townshend adds. "It was actually written about the sanctity of the family, about how revolutions and political changes come and go, but the genetic and natural factors that hold a group of people together -- family -- are irrevocable."

The end, internalized for many years, was not really a surprise: the Who always inspired a "what's next?" aura, particularly since its members were often publicly at each others throats. There had been tours when Roger Daltrey performed with a broken nose (courtesy of Townshend), or when everyone suffered from visibly bruised egos. For many years, rock's adolescent energies were confirmed in the madcap misadventures of drummer Keith Moon, destroyer of hotel rooms and drum sets; rock's haunting tendency to immolation was crystalized by Moon's death in 1978, a victim of drug and alcohol abuse.

But the creative tension within the band, particularly between Townshend and Daltrey, was not only often exaggerated but was almost always revealing, as well. Even now. "I know that Roger and I have a strange relationship, one that we're still fathoming," Townshend says softly. "I read something recently where he get into a Cincinnati concert in 1979. The suicide last year of Kit Lambert, the group's original manager, also took its toll. A year before Moon's death, Townshend had defended the band's longevity and integrity by pointing out that "nobody has killed themsaid, 'Actually, I'm beginning to quite like the guy' . . . you know, this is after 20 years . . . 'but I think Pete still hates my guts.' It's very strange that he should be so . . . misinformed. After 20 years, maybe what I owe him is to stop him one day on the stage, kiss him and say, 'I love you, mate.' I might not show it, but I do. People forget to say it to their f------ wives!"

Things weren't helped by Townshend's intense dislike for touring, or by Who fans who kept tightening the stylistic straightjacket of expectations. With the band wrapped in its own intense tradition, the questions started piling up. "Should we or should we not be so dependent on so much old material?" Townshend asked. "Should we still be trying to evolve? Or dealing with some of the anomalies involved in being in a rock band -- aggression, frustration, youthful sentiments? Should we face up to growing older, middle-aged?" (Townshend, 37, was of course the author of one of rock's most famous lines, "Hope I die before I grow old," in "My Generation.")

"Should we be recognizing the fact that our families were growing up and spending more time with them, not to the extreme that John Lennon did, but perhaps with a trace of that?" Keith Moon's death had shaken the group, as had the death of 11 fans crushed trying toselves off with dope . . . nobody has killed anybody." Reminded of that now, he looks startled. "Did I say that? That's inviting fate, isn't it?"

Along with the personal losses, the creative frustrations mounted steadily. John Entwistle had been the only Who member to put together an outside band (the short-lived Ox), but Townshend almost went the same route after last year's flaccid "Face Dances" album. "It wasn't meant to be an answer to the Who, but to work alongside it. The first two members were girls; I was really keen to break what I felt was the locker-room mentality of rock bands. I wanted to get away from that -- the coarseness, the crudity -- to get an atmosphere and maintain it between songs with a set of musicians who actually lived and breathed what they were working on. But after two weeks of rehearsals, I realized I was in no fit state to run a band . . . and I didn't want to be the leader. I don't think I'll ever form a group on that level; it's one of the reasons I've been thinking about getting into jazz, because a lot of jazz players are used to being temporary and to keeping their ears open."

A release of sorts had come with Townshend's much-acclaimed solo albums; the recent "All the Best Cowboys have Chinese Eyes" was particularly brutal in its self-appraisal after last year's admissions about drugs and alcohol. Both had been present throughout the Who's career, but "it was only in the last year that I started to emotionally have problems. I was getting drunk because I felt I couldn't carry on doing what I was doing, thinking about all those problems. When you question your own credibility, it's quite a long crawl back to any sense of dignity," Townshend says quietly. "I used to laugh at junkies, sneer at junkies; I used to do benefits for junkies, go and get junkies cured, you know? Junkies were a hobby of mine . . . and then I became a junkie. I just never thought that would happen to me.

"I've said that rock eventually kills. It's based on fact, on what I've actually seen. I've thought about it a lot. On this tour, I've said I'm going to come out rich; I might come out of it dead. We could have a plane crash, somebody could shoot me, anything could happen.

"What's worth talking about isn't plane crashes or the Lennon incident, but rock allowing people to destroy themselves in public and applauding them and egging them on up until they destroy themselves in public and then saying, 'Oooh! Why didn't we do something about that?' And I think it's because in rock the people on the stage offer a vicarious experience and you want to push them to the limit, see how far a human being can go. That's why heroes are people that climb mountains; they're heroes if they come back, but they're just as much heroes if they freeze to death at the top . . . just as long as they get there, it doesn't matter if they get back.

"I've often thought about Keith Richards and the Stones. He leads this incredible sort of heavy existence; he's very open about it, lives close to the edge and he survives. But the people around him who try to keep up with him are dropping like flies all over the place. I used to watch people try to keep up with Keith Moon, try to be as funny when they'd drunk three bottles of brandy, try to throw themselves out the same window and get up and walk away; but they'd fall out the window and break their neck and he'd fall out, bounce and then come back and do it again. How did it happen? And he blew it in the end.

"It's important that somebody in rock 'n' roll goes through all that and comes out alive and sane; it's really important."

Within the next year, Townshend plans on coming out alive and sane. There is talk of releasing some of the wealth of demo tapes he has made over the years, and there will be other albums, productions, film work, writing; the spark of creativity will not fade away. The band has even left open the option of reuniting for special concerts.

In the meantime, he may make it back to England in time to see the family business continue. His oldest daughter, Emma, has "a group, the Laundrettes. Their first show's in November," Townshend says proudly -- and with slight, tongue-in-cheek parental disapproval. "I told here the other day, 'I feel as a responsible father I should forbid you to do it. The only thing I understand is performing, and 13 is too early.' " The man who hoped to die before he grew old laughs at himself. And then gets ready for the long goodbye.