The Pittsburgh-based instrumental math rock ensemble Don Caballero underwent numerous line-up changes during their two-decades-plus run. However, the one consistent entity has always been virtuosic drummer Damon Che. The band formed in the early 1990s and released several acclaimed, genre-defining albums for Tough & Go that blended an art-punk sensibility with the technical precision of prog rock and the bombast of metal. The Don went on hiatus in 2000, and guitarist Ian Williams left to form Storm & Stress and, later, Battles. Che reconvened the band a few years later with an entirely new line-up, and released the album WORLD CLASS LISTENING PROBLEM on Relapse Records in 2006.