Rogue Wave have evolved from indie-pop underdogs (2003’s Out of the Shadow) to epic-scale rockers approaching U2 grandiosity (2007’s Asleep at Heaven’s Gate) to confused craftsmen straining for synth-pop relevancy (2010’s Permalight). But singer-songwriter Zach Rogue and drummer/producer Pat Spurgeon regained a sturdy foothold with Nightingale Floors, a set of raw confessional tunes that rebuilt their reputation from the rubble, stripping away the awkward sheen of their previous LP. Now, three years later, they’ve maintained the classic, melodic spark that defined Rogue Wave’s early songs while probing into spacey new territory: While “Falling” defines the project at its core (just Rogue’s soft croon and acoustic guitar, with recording hiss nearly as prominent as the Wurlitzer), “What Is Left to Solve” burrows into an icy synth-rock groove and “Frozen Lake” thaws out shoegaze guitar tones. Delusions of Grand Fur doesn’t boast a timeless indie classic—no “Lake Michigan,” no “Bird on a Wire.” More important, it finds the band charting their DNA and gracefully, subtly tweaking the code.