Dubbed "the king of Canto-pop" for his sensitive and at times flamboyant mastery of Cantonese rock ballads, Jacky Cheung is indisputably east Asia's most popular vocalist. His 28th and latest CD, Kiss Me Goodbye, sold more than 3.5 million copies, including 500,000 in his native Hong Kong (whose population is about 6 million). On tour last year he wowed SRO audiences in China, Taiwan, Singapore, Malaysia, and North America with his supple, limpid voice--an unusual attribute for a singing idol in HK, where a pretty face and a hip attitude can go a long way. He built enormous appeal on an uncomplicated, boy-next-door persona, skidded after a late-80s brush with scandal, and bounced back, Sinatra-like, in the movies, memorably playing a shell-shocked punk in John Woo's Bullet in the Head. In his new incarnation as a mature crooner, he complains about Canto-pop's dependence on covers and its maudlin bent; yet he still sings the songs with mesmerizing effect. At this benefit concert for the Chinese American Service League, his first Chicago appearance, Cheung will perform a medley of recent hits, including a few that use English slang rather idiosyncratically. Sandy Lam, whose voluminous radiant soprano resembles Whitney Houston's, especially in the techno-disco department, will join him for a few numbers. Both Cheung and Lam are good dancers too, though concert choreography in Hong Kong is a lot like that in Vegas: exuberant and kitschy. Friday, 8:30 PM, Arie Crown Theatre, 2300 S. Lake Shore Dr.; 791-6000 or 808-7255.