The real feat of 1996’s “Dopesmoker” isn’t its glacial heft or athletic, hour-long runtime, but the way it continuously shifts while seeming to stand in place. Though Sleep had grown out of California’s doom- and stoner-rock scene, the San Jose band’s fruits have more in common with religious chant or minimalist composition: steady, deep, inherently psychedelic. And while framing weed as a spiritual pursuit is funny (“Drop out of life with bong in hand”), the album’s overall mood foregrounded a reverence and almost monastic focus implied in heavy music going back to Black Sabbath. From sunn O))) to Boris to the profound voids of bands like The Body, Dopesmoker is where modern extreme metal was born.