ZZ Top Cheap sunglasses, fuzzy guitars, slo-mo footwork and all, ZZ Top had a hard time sustaining the rousing crowd response generated by Lynyrd Skynyrd at the Patriot Center Sunday night. Celebrating its 30th anniversary, the "li'l ol' band from Texas" followed Skynyrd's show with all the Southern-fried boogie and blues it could muster. While the trio's new album, "XXX," served as an occasional focal point, the concert was loaded with big hits--"Sharp Dressed Man" and "Legs," among others--and nearly all of them showcased Billy Gibbons's raunchy-toned guitar work. Since its video-primed heyday in the early '80s, the band has simplified its sound and streamlined its concerts. But Gibbons's ferocious tone hasn't lost any of its power or bite, and the boogie patterns relentlessly churned out by bassist Dusty Hill and drummer Frank Beard generated waves of rhythmic momentum. Some of the new and lesser-known tunes, however, were basically interchangeable, and the concert's pacing suffered as a result. Skynyrd's opening set was far more emblematic of Southern rock, fueled in large part by the band's guitarists, Gary Rossington, Rickey Medlocke and Hughie Thomasson. Together and alone, they forged a series of classic Southern rock guitar solos and weaves around singer Johnny Van Zant's husky vocals on both new songs ("Edge of Forever" and "Preacher Man") and such longtime favorites as "Gimme Three Steps," "Sweet Home Alabama" and "Free Bird"--the inevitable and overwrought finale. While not breaking new ground, the band often managed to revive its old hits with a vigor that recalled its glory days. --Mike Joyce *Sent in by the national and international knorn Mr. Michael Crane...s