Everybody knows AC/DC doesn't change much; it tweaks its basic sound from album to album, and that's about it. This time around, producer Brendan O'Brien makes the group sound like live humans playing music in a room rather than gods hurling riffs like thunderbolts from the sky. They're funkier and bluesier than ever before, too; "Stormy May Day" and the title track are fierce groovers, reminiscent of Physical Graffiti-era Led Zeppelin, and "Decibel" sounds like a ZZ Top outtake circa 1974. A couple of tracks (there are fifteen, more than any previous AC/DC studio album) could have been cut, but only four pass the four-minute mark, so Black Ice never drags. Impossible as it may seem, after decades of single-entendre raunch, AC/DC has...aged gracefully. Who saw that coming?