A very young rock group called “The Who” became famous by stomping guitars to splinters, dismantling drums and throwing the pieces at their audiences.

But time mellows all men, even rock musicians. The bloom is off The Who cheeks, the lads are not as young as they were (the eldest is all of 25), and they have turned to, of all things, opera.

* * *

“TOMMY,” the world’s first rock opera—composed by The Who, performed by The Who, and perhaps only completely understood by The Who—has been issued in an album by Decca: four sides, 80 minutes. At the same time, the group is touring the U.S., doing abbreviated versions of the opera and songs from such best-selling past albums as “Happy Jack” and “The Who Sell Out.”

“We don’t miss the violence of our old style,” says lead guitarist Peter Townshend, 24. “ ‘Tommy’ gets the audience up to the kind of pitch we used to achieve by jumping about and smashing guitars.”

The Who had the unfortunate experience of being innovators whom other performers have aped and—worst of all—improved upon. Their guitar-smashing inspired Jimi Hendrix. Their Happy Jack album paved the way for the Beatles climatic “Sgt. Pepper.”

Not that The Who have labored in obscurity. They have been one of Britain’s top grounds for several years, and their records have sold well in America. But until “Tommy,” which may put them in a class by themselves, there has alwys been a feeling of second-best when their performances are mentioned.

* * *

IT IS A four-man group, consisting of Townshend, vocalist Roger Daltrey, 25, bass guitarist John Entwistle, 23, and drummer Keith Moon, 22. They have the lean, long-haired, purposefully ludicrous look of The Beatles, and the same high quality of musicianship.

They are curious iconoclasts, accepting new forms as they tear at the old. Their opera is not grand opera, but it’s good opera in the new rock mold—a successful melange of modernized rhythm-and-blues with new currents of folk, gospel, oriental and burlesqued pop, all bound together with ruthlessly administered blasts of sound.

The hero of “Tommy” is a deaf, dumb and blind boy, untouched and indeed untouchable in his pristine innocence.

Nothing gets through to Tommy, not evil, not pain, certainly not his parents.

“And Tommy doesn’t know what day it is (sings his father)’

Doesn’t know who Jesus was or what praying is

How can we be saved

From the eternal grave?”

Mean Cousin Kevin tortures him. Wicked Uncle Ernie assaulls him. Tommy survives, smiling.

* * *

“HE IS incredibly elated, not disgusted at being homosexually raped,” explains Townshend, who wrote all but tree of the songs in the opera. “He takes it as a move of total affection, not feeling the reasons why.”

By and by, Tommy develops a skill; he becomes a pinball wizard. In one number, a young aficionado wonders:

“What makes him so good? He ain’t got no distractions

Don't see lights aflashin’

Plays by sense of smell

Always has a replay

‘n’ ever tilts at all . . .”

* * *

ALONG ABOUT Side 3 comes a “miracle cure” which may possible have been effected by LSD. Here the plot grows murky. Tommy attaints divinity, starts his own religion, is rejected by his disciples and ends up as alone as at the beginning — and apparently as happy.

“We made Tommy deaf, dumb and blind, so we could give him in the opera everything he hadn’t. He starts off being nothing and ends up being something—divine. People could also be divine, if they would listen to him. Bu they don’t.”

People will listen to the opera, though. The question is: will they hear it?

( “Tommy” lyrics copyrighted by Fabulous Music Ltd. & Essex Music Ltd.)