Known best as a tour guitarist for the metal band Korn, this musician and songwriter also famously founded a Southern California-based rapcore group called Hed PE.
He released Church of Realities, his first EP with Hed PE, in 1995.
Over the course of his music career, he frequently mentored children: he led high school guitar classes and worked as a music teacher for an alternative school called the Fusion Academy & Learning Center.
He and his seven siblings grew up in Fullerton, California, as the children of Eleanor Chamberlain and Wesley Harmon Geer.
In 2009, he replaced Brian "Head" Welch as the lead guitarist for Korn.