An austere, 10-minute epic of ghostly folk-pop that opens Slowdive’s third album, “Rutti” marks a bold departure from the gauzy, reverb-drenched sounds that had been the band’s forte. In its place comes a new awareness of space, silence, and texture—a quality best demonstrated here by the fractured soundscape of “Trellisaze.” Even more compelling is “Blue Skied an’ Clear,” in which a subtly insistent beat anchors the gentle vocals of Neil Halstead and Rachel Goswell as the surrounding sounds disintegrate to eerily gorgeous effect.