SUMAC are a sludge/post-metal band comprised of guitarist and singer Aaron Turner (ISIS, Old Man Gloom), drummer Nick Yacyshyn (Baptists) and bassist Brian Cook (Botch, These Arms Are Snakes, Russian Circles). They released their first album, The Deal, in 2015, through labels Profound Lore and SIGE, and have since released another album, 2016’s What One Becomes, and a 2016 EP, Before You I Appear, both through Thrill Jockey Records.

Turner began writing material for Sumac with the intent of making some of the heaviest music he had ever created, and, once he had the framework of several songs, turned to producer and Converge guitarist Kurt Ballou to help him find a drummer that would fit the music’s style. Ballou, in turn, introduced Turner to Yacyshyn, and after playing together found that their styles matched enough to start a full-time band. After only two jam sessions, Turner and Yacyshyn played their first show in Vancouver, British Columbia, opening for Deafheaven.

When it came time to record their material, Turner employed the services of bassist Brian Cook, initially as a session musician and also for live performances when possible, considering that Cook is also in a full-time band with Russian Circles. However, Cook has since become a third, full-time member of Sumac.

Turner has stated that the music he creates with Sumac is meant to evoke feelings of anxiety and psychological distress, and he purposely avoids using musical devices of cathartic release to alleviate that tension.