The average pop-music fan doesn't know Carl Cox from Wally Cox, but he's been a DJ-culture celeb for almost two decades. A London native, Cox discovered house music circa 1987 and went on to became a prime spinner in Britain's influential rave scene. He eventually developed into a salable commodity, as proved by the success of F.A.C.T. , a 1995 mix disc that shifted a quarter-million units -- and while the dance movement headed back underground shortly thereafter, he continues to be a name draw across the globe. Cox is nearing the end of a North American bus tour with the likes of Loco Dice, a onetime Dusseldorf fixture who will join him at the deck during his Denver visit. The plan is to raise Cox's profile in anticipation of Second Sign, a disc set for release next year that will feature cameos by Misstress Barbara, Roni Size and Norman "Fatboy Slim" Cook. Duplicating the popularity of F.A.C.T. will be a challenge. After all, even Fatboy's last platter didn't exactly set the Billboard charts aflame. Yet no matter the album's fate, Cox will still be a star in the dance world, if not in the universe the mainstream runs through.