It’s hard to believe that a band as seemingly simple as Low continues to evolve a quarter century into their career, but here we are. Their second album with Bon Iver producer B.J. Burton, Double Negative takes the band’s basic sound (slow, spare, but taut with drama) and fills the space between notes with ambient rumbling, often turning the music into a kind of palimpsest—a beautiful song hidden inside crumbling sound. If anything, what makes the album so unsettling isn’t its sense of silence, but of continuous noise, so subtle you might mistake it for a distant train or footfalls in the hall. Still, the anchor is the writing and interplay of Mimi Parker and Alan Sparhawk, whose best songs—Parker’s “Fly,” Sparhawk’s “Dancing and Blood”—explore the human condition with a frailty and sense of low-grade horror that has always set them apart.