The Wartburg Choir will preview its program for a five-state Midwest tour at a home concert Sunday, April 7.

The 77-member choir will sing at 4 p.m. in the Wartburg Chapel. Admission is a free-will donation. It will tour Iowa, Minnesota, South Dakota, Nebraska, and Colorado, April 19-28.

Dr. Lee Nelson, choir director and associate professor of music, said the program tour repertoire was inspired by Frank Martin’s “Sanctus” and is structured around the Mass Ordinary, a group of texts that form the structure of the mass.

“Using the Mass Ordinary as the concert framework, the choir will perform a wide variety of music, singing different styles from different musical periods in sets arranged around movements of the mass,” Nelson said.

The program will begin with works from famous composers, including Johann Sebastian Bach and Joseph Haydn and features a “space music” piece for triple choir, “Me-Na-Ri,” by Korean composer Hyowon Woo to depict the program’s “Credo” set.

Nelson said a pivotal moment during the “Agnus Dei” set is Veljo Tormis’ “Curse Upon Iron,” inspired by the recent school shootings in Newtown, Conn.

He described “Curse Upon Iron” as  “a very visceral piece that uses nontraditional harmonies and movement by the choir to capture the sentiments of anger and destruction This is followed by ‘When David Heard,’ which is filled with mourning and solemnity, and finally, the promise of grace and mercy revealed in F. Melius Christiansen’s setting of ‘O Day Full of Grace.’”

The program ends with the message “Ite Missa Est,” meaning,“Go and Spread the Good News,” featuring new works by Stacey V. Gibbs and Connor Koppin, a senior member of the choir from Mason City.