While many groups wear their influences on their sleeve, Austin’s Shearwater defies typecasting. The band’s dramatic musical arsenal spares it from making mere pop Xeroxes: Singer Jonathan Meiburg plays with eerie falsettos and operatic growls; the group’s swoops and leaps in volume are like a symphony’s (albeit one with electric guitars and booming drums). Shearwater has honed its approach over a decade, and its sixth album, The Golden Archipelago (Matador), is impressive. Meiburg is a devout naturalist, and the material is sea-soaked, focusing on the world’s islands, their fate at the hands of man, and man’s ultimate fate at the hands of nature. Lyrically, there’s menace and foreboding, but there’s also a Paul Bowles—like global curiosity (the CD comes with a fifty-page travel dossier). Heady stuff, but it’s buoyed by lush arrangements (“Uniforms”), Steve Reich–style minimalism (“Hidden Lakes”), and moments of riveting intensity (“Black Eyes”). Songs are short, and some come off as fragments. But when, as on “Castaways,” the band rolls all its strengths into a three-minute burst, the results are breathtaking.