“The Knave,” the second track of Collin McKelvey’s ambitious new C78, The Golden Ass, has moments whose uncanny beauty is difficult to put into words. The reserved composition employs manipulated string drones, digital processing and synthesis, and source-obscured recordings, all tools with which McKelvey often works; but here the combination reaches incredible depth and resonance, as the woody drones flit across what sounds like a creaking ocean liner until they are the only thing remaining in the mix, the tones stretching, straining between your ears until the track ends quite unceremoniously with an unsettling clip of laughter. “The Knave” is only one of four tracks on The Golden Ass, but it is perhaps the best possible representation of McKelvey’s mastery over the sounds he uses. The music throughout the tape is well-composed, almost approaching contemporary electroacoustic composition in scope, but with a pleasing roughness and grit that makes it much more personal. Even in the quietest stretches there is a captivating coexistence of tension and beauty, and you’re never sure whether the grainy constructions will spiral out of control or softly vanish. Don’t be intimidated by the length; McKelvey makes these 75 minutes feel like much less. This wonderful journey awaits you.