It's hard to top the heaviness-per-square-sonic-inch of Slipknot's second album, I.O.W.A. So Slipknot doesn't bother trying. Presumably bored with out-ghouling the competition, the horrific heshers take a few left turns on Subliminal. Songs such as "The Blister Exists" feature everything a diehard 'Knothead could ask for: blast beats, militant percussion, gear-stripping guitars and vocals from Corey Taylor that alternate between strep-throat screams and so-crazy-I'm-talking-to-myself gibberish. But the hype about Subliminal is that producer Rick Rubin pushed the band in new directions, unearthing untapped potential within the nine-piece group. That's true on "Circle," which is awash in acoustic guitars, violins and vocal harmonies -- a cool moment for a group whose image often overshadows its music -- but it also leaves the band with little to contribute. I doubt the Clown handled violin duties. It's also disappointing to find that Rubin's guidance wrought few changes. That might reassure the band's faithful maggots, but it's also a lost opportunity to find out what these masked men could concoct if they really tried to forge something different.