Olympia band Earth's quarter-century-long existence encompasses two major periods of productivity, one temporary hiatus, and dogged reliance on one tool: the riff. The band, a project of Northwest native and Kurt Cobain cohort Dylan Carlson, repeats riffs past the point of absurdity and into the realm of mantra. 1993's Earth 2, a kick-off for the drone metal subgenre, is three laser-guided meditations on distortion and tonality. Imagine playing a Howlin' Wolf record through a fuzz pedal at 16 RPM, and you get close to the idea. Earth's second major ditches the distortion and uses brute tonality to get ideas across. Earth, along with musicians like Portland's ambient explorer Grouper and Salem's longform metal outfit Hell, belong to a special category of Northwest drone. MAC POGUE Also, read our article on Super Furry Animals.