Logan Conrad Mader (born November 16, 1970 in Montreal, Quebec, Canada) is a record producer and current guitarist in melodic death metal band Once Human, as well as former guitarist in groove metal band Machine Head, which was formed in Oakland, California in 1992. Mader is most famous for his time in Machine Head, whose 1994 debut, Burn My Eyes, was released by Roadrunner Records and quickly became the top-selling debut album in the label's history until Slipknot's debut album.