THEY MADE THEIR first appearance in a London club in 1964, with lead singer Roger Daltrey shouting his lungs out while guitarist Pete Townshend committed mayhem with his guitar, bashing it into the amps until the hapless instrument split in two. By the time they made their United States debut in 1967, they had several hits behind them, and when their rock opera "Tommy" was finally released a few years later, worldwide fame was theirs.

The Who have been on the scene a long time. But while groups have come and gone, and others, like the Rolling Stones, have turned into caricatures of their earlier glories, the Who have survived—and continue to triumph. They are, very probably, the most high-energy group of all, as well as one of the loudest. Thursday they appeared at the Chicago Stadium for the first of two nights there. Ears are still ringing, and the energy lingers on.

THE GROUP'S repertoire has changed little in the last few years. Thursday night, Daltrey, Townshend, bass player John Entwistle and manic drummer Keith Moon charged through some material from their new album, "Who by the Numbers," but they didn't neglect the old staples—"My Generation," "Baba O'Riley," and "Won't Get Fooled Again," the dynamic finale accompanied by a lighting effect of dozens of laser-type beams that split the air in thin green and red lines. They also included a good bit of material from "Tommy," with "Pinball Wizard" a predictable high point.

Their stage presence, too, was predictable. Daltrey swung his microphone by the cord in ever widening arcs; Townshend made his familiar windmill arc over his guitar string with his arm, and he continues to leap into the air like a raving rock 'n' roll cheerleader. Meanwhile, Moon drummed for all he was worth while Entwistle stood quietly by like a statue with his bass, only his fingers moving.

The Who's Roger Daltrey: Energy you could almost reach out and touch.

And that wonderful energy, so real you could almost reach out and touch it, transcended everything. The Who are well past their teen-age years, though their songs are still ones of youthful rebellion and adolescent revolution. But they show no signs of slowing down with the years, and they still embody the spirit of rock 'n' roll at its finest.

THE SHOW OPENED with a shot of reggae music from Toots and the Maytals, who appeared not too long ago at the Quiet Knight. The Stadium's larger stage suited them, and though as reggae bands go they'll never measure up to the excitement of the Wailers or the soulful charm of a Jimmy Cliff, they were often more than OK. But do they have to do John Denver's "Country Roads, Take Me Home"? Old Smiley-face has crept into country music, but the thought of his saccharine songs set to a reggae beat borders on the sick making.