Swooping In and Out With Texas’ D.O.C. : THE D.O.C. “Nobody Does It Better.” Ruthless /Atlantic: *** 1/2: POP STARS: ***** Great Balls of Fire: ***** Knockin’ on Heaven’s: *** Good Vibrations: ** Maybe Baby: * Ain’t That a Shame

Hip-hop, like disco, is essentially a producer’s medium, and it’s often more accurate to rave about a Matt Dike sound or a Teddy Riley sound than about a Tone Loc or a Kool Moe Dee. This year’s hot hard-core hip-hop sound comes from Dr. Dre, the Compton-bred deejay behind Ruthless Records, which in the last several months has released million-selling rap LPs by J.J. Fad, Eazy-E and N.W.A.

The D.O.C., a Texas rapper who led the undistinguished electro-hop posse Fila Fresh Crew, is Ruthless’ newest artist, and Dre has transformed him into something of a Compton-style Big Daddy Kane, a guy who plays the English language the way Itzhak Perlman plays a Strad. The D.O.C.’s lyrics cut and his rhymes are fresh, while his mild voice functions almost as a rat-a-tat obbligato that rhythmically supports the groove, swooping in and out of the beat.

Though his subject matter tends toward loud boasting, his raps submit absolutely to the tyranny of the beat box, which itself supports funky riffs lifted from the likes of Parliament and the Sylvers. Label-owner Eazy-E and the rest of N.W.A are generous with the cameo appearances we’ve grown to expect on any Ruthless release.