The Archdiocesan Festival Choir of Atlanta celebrates its sixth season with a wildly diverse program “Alleluia—Songs of Devotion and Praise” on Saturday, April 26, at 8 p.m. at Holy Spirit Church, 4465 Northside Drive, NW.

The program will feature several traditional Marian chants as well as motets by Bruckner, Biebl, Aichniger, Dupre and Thompson, and will be highlighted by works for large brass ensemble, organs and chorus by Giovanni Gabrieli and John Rutter. The public is invited. Tickets are available online or at the door for a suggested donation of $15. Holy Spirit is located at the corner of Northside Drive and Mount Paran Road.

The Festival Choir, a long-held dream of many Catholic musicians in the area, was formed in 2003 with the express intent of uniting singers from parishes all over the archdiocese. Open auditions have been held each year, and dozens of singers have come forward to lend their voices to the choir.

“The whole experience has been an incredible joy,” said singer Jean Nash from St. Thomas the Apostle Church in Smyrna. “Each rehearsal, each time we get together, we meet new friends and make new music. … It has been tremendously energizing.”

Wayne Baughman, director of music at St. Benedict Church in Duluth and principal conductor of the choir, said it “has met and exceeded all of our expectations. … Our highest hope was that each singer’s love of music would be enriched and their faith deepened by the experience.”

This year’s concert prominently features four works that explore the use of multiple choirs and ensembles.

The program opens with Marcel Dupre’s “Laudate Dominum,” which blends the great organ in the rear balcony at Holy Spirit with a smaller organ supporting the choir at the front of the church. Englishman John Rutter’s “Gloria” for choir, soloists, brass and percussion orchestra, and organ is the featured work of the program.

“This impressive work leaps from one dramatic climax to another, but moments later can portray a lovely simplicity,” Baughman said.

Also on the program is a motet by Giovanni Gabrieli, the acknowledged master of spatially separated choirs. The work is “In Ecclesiis,” a sacred symphony for 15 voices.

For decades the composers for St. Mark’s Basilica in Venice, Italy, were experimenting with multi-voiced forces for their liturgical music, and Gabrieli became the most famous proponent of the style. Musicians from all over Europe came to study this music, and the “Venetian style” is evidenced throughout the late Renaissance and early Baroque periods.

Kevin Culver, choirmaster at Christ the King Cathedral, said that in this work the composer “mixes and matches” the voices of six brass players, three vocal soloists, an organ, and a four- to eight-part choir “to create a shimmering mosaic of sound.”

Of a more subdued nature is the internationally beloved “Ave Maria” by Franz Biebl. This work, composed in 1964, presents the traditional Annunciation text in the most gentle of fashions, sung by a trio of soloists supported by the full chorus.

This work is one of six Marian pieces that are on the concert program. Of particular interest are two traditional Marian chant antiphons “Ave Regina Coelorum” and “Regina Coeli.”

Culver said that “through the passage of this century, the four traditional Marian antiphons, once known to all Catholics, have almost lost their voice. The only one that really remains in the collective consciousness is the ‘Salve Regina,’” sung during Ordinary Time from Pentecost to Advent.

But the other three— “Alma Redemptoris Mater,” which is sung from Advent through the feast of the Presentation of the Lord, “Ave Regina Coelorum,” sung from Feb. 2 through Lent, and “Regina Coeli,” sung from Easter through Pentecost, “are all lovely tunes and simply await rediscovery,” Culver said.