Aaron Turner is an American musician, singer, graphic artist, and founder of label Hydra Head Records. He is most widely known for his role as guitarist and vocalist for the post-metal bands SUMAC and Isis, while also participating in several other bands and projects such as Old Man Gloom, Lotus Eaters and Split Cranium, a collaboration with Jussi Lehtisalo of Finnish band Circle who toured with Isis in 2009.

Post-metal is a music genre rooted in heavy metal but exploring approaches beyond metal conventions while being related to and similar to post-rock. It emerged in the 1990s with bands such as Neurosis and Godflesh, who transformed metal texture through experimental composition. In a way similar to the predecessor genres post-rock and post-hardcore, post-metal offsets the darkness and intensity of extreme metal with an emphasis on atmosphere, emotion, and even "revelation", developing an expansive but introspective sound variously imbued with elements of ambient, noise, psychedelic, progressive, and classical music, and often shoegaze and art rock. Songs are typically long, with loose and layered structures that discard the verse–chorus form in favor of crescendos and repeating themes. The sound centres on guitars and drums, while any vocals are often but not always screamed or growled and resemble an additional instrument.