Aaron Turner—of the legendary Isis, and also the founder of Hydra Head Records—joined forces with Russian Circles' Brian Cook and Baptists' Nick Yacyshyn in 2014 to form the band Sumac. Now they're getting ready to put out Sumac's second album, What One Becomes, due on Thrill Jockey in June. It's an igneous record of stripped-down parts (drums, bass, guitar, and Turner's hoary howl) that have been blown up to stratospheric scale, emphasizing the power of essentially simple ideas after they've been turned up to incredibly high volumes. As such, Sumac have found a fascinating point of musical unease, located somewhere in between metal's groove, post-rock's precision, noise's antisocialism, and prog's often over-ambitious desire to sound bigger than the sum of its parts. Sumac live in a place where repetition and space turn into sonic suffocation—you'll either be terrified or thrilled. NED LANNAMANN