In the Absence of Truth is the fourth full-length studio album by Los Angeles, California-based post-metal band Isis, released by Ipecac Recordings on 31 October 2006. Vinyl release was handled by Conspiracy Records.The album expands upon the group's previous full-length, Panopticon, further exploring lead singer Aaron Turner's clean vocals (though his former techniques, which relied more on screaming and growling are still present as well).