“Let’s go where no one can see us and find the difference between us,” sing Jack White and Alison Mosshart on Sea of Cowards, the second album by Dead Weather, the supergroup featuring White and Mosshart, along with Dean Fertita (Queens of the Stone Age) and Jack Lawrence (the Raconteurs, the Greenhornes). And what is that difference, exactly?

Mosshart, of the Kills, has a great rock ’n’ roll voice, sexy and scary. White, of course, is the singer-guitarist of the White Stripes, with whom he puts on an image that’s part old bluesman, part rock ’n’ roll wild man, and part innocent child. In the Raconteurs he plays the part of musical craftsman. In Dead Weather he tries out an image that’s vaguely satanic, but mostly just sexy and scary. You can hardly tell the difference between him and Mosshart when they’re singing.

For that matter, there are times when you can hardly tell the difference between Dead Weather and the White Stripes — or at least later White Stripes. But Dead Weather goes farther down the route the Stripes took on Icky Thump. Keyboards are a big part of Dead Weather’s sound — weird, old keyboards distorted to the point where it’s difficult to distinguish them from the squealing guitars. The sound is something like Led Zeppelin meets Deep Purple, with heaping tablespoons of Black Sabbath. At its best, this is very powerful stuff. Dead Weather doesn’t push White or Mosshart in new directions, and the supergroup won’t win any songwriting awards (what is “cut like a buffalo” supposed to mean?), but they will kick some ass before they wear out their welcome.