These five Tucson choirs come together as a mass ensemble under the direction of Dr. Elizabeth Schauer to perform excerpts from Terza Messa by Marianna Martines in preparation for their upcoming performance at Carnegie Hall. (Directors of the choirs include Dr. M. Nicole Davis, University Singers; Chris Newsom, University/Rincon High School; Suzi Barnes, Sahuaro High School and Rachel Lovins, Ironwood Ridge High School)