The Phoenix Chorale and Tucson's True Concord (pictured) will perform the Requiem by Maurice Durufle and Frank Martin's Mass for Double Choir Sunday, October 13 at Camelback Bible Church in Paradise Valley. Phoenix Chorale's Artistic Director Christopher Gabbitas and True Concord's Music Director Eric Holtan recently came into the studio to chat with KBACH's Greg Kostraba about the reasons for their first-ever collaboration, and the music they will be performing.