Simon Hafner (Simon/off), is a musician, DJ, radio host an a member of music collective disko404.

His numerous releases appeared on various domestic and international labels. He has performed in Mexico, Lithuania, Bulgaria, Germany, Belgium, Great Britain, Switzerland and Slovakia, among others. He has been active in the Graz cultural scene at various levels over the past 15 years. Among others for the Steirischer Herbst and the Forum Stadtpark as well as for the Elevate Festival since 2008. In 2013 he was elected to the board of IG Kultur Steiermark and has since been active in the state representation of IG Kultur Austria.