Roback was active in the Paisley Undergroundindie music scene in Los Angeles in the early to mid-1980s as leader of the band Rain Parade, which was popular on the local club circuit. Shortly after the release of their debut album in 1983, Emergency Third Rail Power Trip, Roback left Rain Parade to join Rainy Day, a collective featuring other musicians from the Paisley Underground. Their first and only album was issued in 1984, which also featured contributions from The Dream Syndicate vocalist Kendra Smith. That same year, Roback and Smith formed Clay Allison, changing that band name to Opal by the time they released their debut album in 1987, Happy Nightmare Baby. While promoting the album, Smith acrimoniously exited the band while they were partway through a tour opening for The Jesus and Mary Chain. She was replaced by Hope Sandoval, but this lineup never released an album; they changed the name of the band to Mazzy Star in 1989. Mazzy Star released three albums in the 1990s: She Hangs Brightly, So Tonight That I Might See, and Among My Swan, making their commercial breakthrough with the 1994 single "Fade into You" before going on hiatus. In the years that followed, Roback produced and recorded music with other artists: he produced songs on Beth Orton's 1999 albumCentral Reservation and performed on Bert Jansch's 2006 album The Black Swan, among others. Roback wrote and produced the songs that actress Maggie Cheung sang in the 2004 filmClean. He also played himself in the film. He spent much of his later life in Norway, where he collaborated with various musicians and created original music for art installations. He reunited with Sandoval to release Mazzy Star's fourth studio album in 2013, Seasons of Your Day, followed by the 2018 EP Still, which was promoted with a three-night residency at the Sydney Opera House. Prior to his death, Roback had been working with Kendra Smith on re-releases of Happy Nightmare Baby and a compilation of Opal EPs titled Early Recordings, both of which are "imminently" due for release via INgrooves.
Roback's songwriting and guitar work has, according to Alexis Petridis of The Guardian, been highly influential, "most strikingly on Lana Del Rey: you could clearly detect shadow... on her breakthrough album Born to Die, a more explicit examination of the LA darkness that had always lurked somewhere in Mazzy Star's sound. In turn, Del Rey went on to exert a vast influence of her own, which meant that one of the most reticent bands in recent history ended up becoming a part of latter-day pop's musical DNA."