Friends since middle school, Brendon Anderegg and Koen Holtkamp both attended the School of the Art Institute of Chicago, started the experimental Apestaartje record label, and have been recording as the electroacoustic duo Mountains since 2005. On albums such as Sewn, Air Museum, and Mountains Mountains Mountains, Anderegg and Holtkamp take listeners on intriguing ambient sonic adventures combining acoustic guitars, keyboards, electronics, and environmental sounds, creating layers that seamlessly flow together. On their new album, Centralia (Thrill Jockey, January 23), the Brooklyn-based duo has concentrated more on the individual elements that go into their excursions, which can run more than twenty minutes, as on “Propeller,” in which a live song has been transformed into a beautiful, epic trip through nature, ending up on a beach with soft waves rolling onto shore. “Tilt” shows off Mountains’ more folky side, while “Liana” heads off into outer space. Centralia, which is currently streaming for free at Pitchfork, is a soothing, meditative journey that goes wherever you allow it to. Mountains will be holding a record release party January 19 at Union Pool on a bill with Mind over Mirrors, Golden Retriever, and East Village Radio DJ Jeff Conklin.