If two friends of each performer in Sunday’s “Everybody Sing!” concert show up at Orchestra Hall, there will be more than a thousand partisan supporters in the audience.

The 4 p.m. concert will officially close the 40th anniversary year for VocalEssence, which has been a big season of big events, including a tour of England. But choral music enthusiasts -- and there are a lot of them around here -- also will have the chance to hear six other choirs singing under the same cube-encrusted roof in downtown Minneapolis.

And there’s more: 500 voices giving the world premiere of a new work by Minnesota’s preeminent composer, Dominick Argento.

Here’s the program lineup: Each of the choral ensembles will sing a work from its own repertoire, plus one work that was premiered or commissioned by VocalEssence during its 40-year history. Then all the groups will form a mass choir to perform Argento’s new work -- which carries the ironic title, “The Choirmaster’s Burial.”

Actually, it’s an unaccompanied vocal setting of a poem by Thomas Hardy, and I’ve been told it’s not the "downer" that the title implies. Ironic, yes. Downer, no. For ticket information, go here, where you can also listen to a podcast.

Here are capsule descriptions of the participating groups:

VocalEssence: Founded by Philip Brunelle (it was called The Plymouth Music Series back then), the ensemble includes a 130-member chorus and a 32-member choir called the Ensemble Singers.

Kantorei: A 40-member a cappella choral ensemble originally founded by alumni from the College of St. Benedict and St. John’s University, conducted by Axel Theimer.

Magnum Chorum: Inspired by the choral tradition of St. Olaf College, specializing in performing in cathedrals and sanctuaries; directed by Christopher Aspaas.

Minnesota Chorale: Founded in 1972, the principal chorus of the Minnesota Orchestra; led by Kathy Salzman Romey.

National Lutheran Choir: Conducted by David Cherwien, specializing in Lutheran choral traditions.

The Singers- Minnesota Choral Artists: Just five years old, it already has premiered 28 new works; founded by Matthew Culloton.

Twin Cities Gay Men’s Chorus: Formed in 1981, the ensemble numbers 140-members, making it the fourth largest gay men’s chorus nationwide.