True love for hard core rock and roll is a deep and enduring thing. Like Tommy's love for Laura it is something--once you've got it--that never really dies.

Ever since Sha Na Na burst upon the national rock-and-roll scene with its tour de force performance at Woodstock, I've been an infatuated follower of the group's fifties style and sound. In the wasteland of electric rock Sha Na Na provided a welcome retreat from the overblown basses and haranguing lead guitars that were pummelling listeners of contemporary rock music with monotonous uniformity. They captured me in that first performance, launching what has become an enduring and passionate romance.

Sha Na Na has come a long way since the group took its first faltering steps out of Columbia into the big leagues of commercial entertainment. And today, having struggled through years of raised eyebrows and quizzical looks, not to mention near anonymity, Sha Na Na has reached the summit of the popularity charts, commanding top billings and superstar payoffs. The days of three-in-a room road trips and one-night stands at the Boston Tea Party have been replaced by opulent concert tours and million-seller records.

But success and Sha Na Na's brand of music were not immediately compatible. The demands of the group's 170-concert-a-year schedule brought with them a kind of stagnation to the Sha Na Na product.

By last spring, when the band appeared at an MIT Budweiser Beer Blast, Sha Na Na's performance had declined into a slick, mechanical facsimile of its former self. The choreography, once supple and evocative, had become stilted and sticklike. The songs, once emotional and exciting, seemed rushed and dispassionate. The group's enthusiasm seemed dulled.

Since last spring's lusterless performance at MIT Sha Na Na has undergone some serious renovation. Realizing that performance and image were going down the drain with its new-found success, Sha Na Na has rejuvenated its act.

The new show, which Sha Na Na promoters are boosting for a run on Broadway, opens in the traditional Sha concert style. Highlighted by the Three Men in Gold, the band blitzes through a series of oldies--from "Yakety Yak" to "Tell Laura I Love Her," from "Splish Splash" to "Tears on My Pillow."

From there, though, Sha Na Na heads off onto a whole new tangent that is more theater than concert. The second act, "Sha Na Na Hits the Street," features props and backdrop assimilating a New York streetscape, complete with lit lamp post, brick wall scrawled with initials and obcenities, and a clothesline dangling scraggly threads. Act two then moves to a hop and ends with a dance contest emced by Bowzer in which three members of the band choose partners from the audience.

The third act winds up the show in a frenzied carousal--with Three Men in Blue (transformed from gold)--through some fast and furious renditions of Sha Na Na's best numbers.

But more important to the revival of Sha Na Na than the change in format, is a new attitude and style. The group has slowed down its entire performance. Sha Na Na no longer sprints through its program like a runaway street car. The songs that had become mechanized and two-dimensional are now calmer and more personal. Of course, the group has had to sacrifice quantity for quality, but it is a sacrifice that rock and roll lovers everywhere should welcome.

What the change in format, the more relaxed atmosphere, the new material indicate is a marked shift toward the theatrical in Sha Na Na's act.

The change in the group's concert format is concomitant with an evolution in the character of the crowds that flock to see Sha Na Na. No longer do gobs-of-grease coiffeurs glisten as the lights pan over the audience; bobby sox and saddle shoes are practically non-existent now.

Sha Na Na has stopped capitalizing on grease for grease's sake. Today the group draws crowds for its music not for the gimmickry and novelty of Brylcreme or gold lame. The group's musicians hip and singing abilities are now the basis for Sha Na Na's appeal.

The new Sha Na Na show is a good one. It combines theatricality and personal warmth with a welcome deceleration in the tempo of its numbers to provide some real satisfaction for the rock-and-roll lover. But while the new format is refreshing and novel, it is the change in the music itself that makes Sha Na Na's new concert worthwhile.

"Tears on My Pillow" slowed down and personalized into a poignant depiction of lost love is simply tremendous, as is "Teenager in Love" in which (swear to God) Chico actually cries. New numbers "Sha Boom" and "Summertime" are welcome deviations from the traditional Sha repertoire. "Summertime" particularly, with Johnny "Kid" Contardo once again revealing how versatile and disciplined his voice really is, is superb.