Headlining a post-SXSW metal-thon at the Austin club Red 7, the Pacific Northwest band Wolves in the Throne Room made their feral noise — double-guitar drone and machine-gun riff spray, mounting-thunder drumming, singer-guitarist Nathan Weaver’s burnt-throat bellow — in a dramatic half-light cast by candelabra onstage. The band’s third album, Black Cascade (Southern Lord), is distinguished, too, by the depth of its shadows: the outbreaks of melody and harmonic reach in “Wanderer Above the Sea of Fog,” the creeping-dawn climax of “Crystal Ammunition.” Weaver’s vocals are all fury, no pronunciation. But the snarling om and peaking shriek of his and Will Lindsay’s guitars are eloquent terror.