Like Trent Reznor after him, Sisters of Mercy's Andrew Eldritch has never lived up to the purported extremism of his image. Beneath the shadowy visage of Arctic vocals, soundscape-y arrangements and morbid obsessions, his rotating British band is just a rock group and a pop-rock group at that. That goes not only for the 1987 hit "This Corrosion"--which, sans fog, breaks down to something close to a funky Bowie tune--but also 1984's "Walk Away," a pretty conventional verse-chorus-verse about romantic fidelity set to hollowly arpeggiating guitars, and virtually anything else Eldritch has recorded with his rotating cast of sidemen (and women). But the effects in which he swaths his pop do serve a purpose, lending his records the kind of grandeur that works better on the Phil Spector oomph level than the dark, exotic one that's probably drawn so many of his fans. With a formidable catalog of LPs and EPs to draw from, Wednesday's show promises hooky, pompous fun.