Simple but explosive juxtapositions are at the root of North's compositions — emotionally driven metal that asks its audience to surrender. Not to surrender in any kind of spiritual way, but to literally surrender to the band's aggressive vocals and post-metal bombardment. Songs such as "Eidolon" usually begin understated, as setup to a not-so-surprising metal crescendo. Cue the affected-vocal temper tantrums. (Pay special attention to the screaming call and response, a new take on an old blues tradition.) The vocals are so violent that you're likely either to drop into the fetal position and ask for your mom or wonder whether they're some kind of bizarre parody of the Cookie Monster. They say flashing red lights can cause seizures. There's the mythical "brown note." There must be some urban myth surrounding metal like this — like spontaneous group self-flagellation. Folks leaving the show beating themselves about the head . . . No matter; you'll have to surrender. There really isn't any middle ground with North — you're always at one extreme or the other, because subtlety isn't really the point, is it?