Stay up channel-surfing some night and you might run across an old episode of It's Showtime at the Apollo. On it, a boyish rap duo throws down some goofy rhymes over deep, dexterous scratches and beats. The mixmaster is a zit-faced kid named DJ Jazzy Jeff; the MC is some scrawny dude with big ears who probably couldn't win a freestyle competition against a robot. Nonetheless, Jeff Townes -- as one half of DJ Jazzy Jeff and the Fresh Prince -- helped bring hip-hop to the mainstream in the late '80s with a string of Grammys and multi-platinum albums. After the twosome disbanded in 1993, Jeff formed A Touch of Jazz, a production house that's worked with everyone from Lil' Kim to Michael Jackson. In 2002, he released Magnificent, a blend of liquid beats and crisp, jazzy soul, while this year's Hip Hop Forever Vol. 2 is a mix of some of Jeff's favorite beats from his decades behind the decks -- a few of which will surely pop up in his set this Sunday at the Church. If you can't make it down, you can always try catching that rerun of Showtime. But as you watch the young DJ's already formidable skills eclipse everything else on stage, you might wonder to yourself: What ever happened to that other guy?