Eleven rock fans were trampled to death as a crowd of 7,000 teenagers surged towards the gates of the Riverside Coliseum in Cincinnati where The Who group was tuning up. No one was more appalled than Pete Townshend, the group's leader. Townshend, now 35, has grown disillusioned by these mass rock concerts and the wild expectations of the audiences which attend them. His disgust for the life of drugs, drink and sex — a rock cliche for the past 15 years of his career — coincides with a feeling that in this atmosphere nothing creative can be achieved.

LONDON — In the old days there was no need to coax Pete Townshend onto a stage. Fifteen years ago, when he was the authentic voice of teenage frustration and aggression, he proved it most nights by doing ritual damage to low ceilings, speaker cabinets and his guitar; he was happy to see himself set up then as the spokesman for a generation. The music The Who played was "auto-destructive," he said; it was "Pop Art," and "cybernetic."

"When I get the feed-back noise," Townshend said, back in 1965, "it sounds like a bomber; then Moon (the group's late drummer) can bang the drums and the audience thinks of guns and smashing people up... they envy our music. They would like to get hold of a $400 guitar and wallop it. They would like to jump on the stage and yell about why can't the kids have pills, and why the young are being put down by people of 40 who want to be 20. We're catering for their suppressed aggression."

Unlike most of their contemporaries, The Who established a reputation not through records, but through performing. Increasingly, however, as time went on, Townshend was forced to realize that The Who's performances had changed people's lives.

When 7,000 of The Who's fans ran amok in Cincinnati, they were trying to get as close as possible to a legend.

But that legend today is a father of two and the husband of a schoolteacher in Kingston-Thames, Surrey; his idea of the perfect concert is one he can get home from in time to sit down with a cup of tea. The Who's current tour of America is being staggered so that Townshend can make regular trips back to London to see his family.

"Mine is not the archetypal rock star life," Townshend said some months ago, when it was still unclear whether The Who would ever perform in public again. "I really do feel that there's a certain age beyond which you can't — no matter how much your audience might will you to — do the standard rock 'n' roll thing. Take a look at those who disagree with that, and what do you see? A 'load of decrepit, pasty-faced, half-dead people. I mean, I don't like watching Mick Jagger on television."

It was at the end of The Who's last tour of North America, in 1976, that Townshend, always Keith Moon's accomplice in excess, started to feel he had been pushed far enough along a road down which he had seen too many others travel: he was physically debilitated and near-alcoholic.

"And I found it," he said, "totally, morally degrading. It was the antithesis of everything I strive for. Especially as, all the time, the fans were saying the kind of dumb things they're still saying now, which is that it's all very simple: you just go out there and rock 'n' roll, and that's all life is about. Which, of course, is nonsense."

It is this Pete Townshend, reasonable adult, and a longtime devotee of Indian teacher Meher Baba who found expression in the songs that comprise his rock "operas," Tommy and Quadrophenia.

But it was the constant repetition of Tommy, and the programmed response of its audiences, that started his disillusion. He came to feel that The Who had become merely a celebration of their own past.

"It's very easy," Townshend said, "to go on the stage, play the opening chords of 'Can't Explain,' and get instant joy and happiness in the first 20 rows. Follow that up with 'Summertime Blues,' then the laser, see me, feel me ... 'My Generation,' an out they go. Hurray! You don't have to do anything new. Which is what I find unbelievably frustrating. The fact that it's all so easy. It's like being the queen. You know that it's nothing."

Townshend's immediate response to the Cincinnati disaster was that, had The Who been performing when it happened, he would never again have set foot on a public stage. As it is, they will go on playing, but their days as a touring unit are almost certainly numbered.