Altar

This collaboration between the power-ambient Sunn 0))) and Japan’s experimental sludge rockers Boris, with guests including members of Earth, High On Fire, Soundgarden and Jessamine, is one slow, heavy and loud affair. 2006’s Altar makes ambient music for metalheads and stoner-rock fans, but it’s quite effective for anyone looking to experience music as an altered mental state. Guitars and synths rarely venture beyond a few chords, settling on sounds that sustain for long periods of time. Jesse Sykes adds her atmospheric vocals to the album’s breather, the 4AD-like jangle of “The Sinking Belle (Blue Sheep),” for a slight lift from the dense orchestral fog. “Etna” grinds with inspired intensity. “N.L.T.” rattles like deep, purring thunder. “Akuma No Kuma” returns the festivities to more mind and body melting drones while a robotic vocal adds to the disembodied feel. But the key track here is the closer, “Blood Swamp,” where all the beauty and the subliminal voices come together for a near fifteen-minute drone that under headphones transports the listener to the darkest recesses of the mind. Amazing and darkly sublime.