Ars Nova Singers will push the boundaries at 'Rebirth' concert, presenting monumental motet rarely heard live

Feb. 3—When going to a history museum, it's rare — almost impossible — to see a relic of significance in action. For instance, museum guides hardly volunteer to hang themselves from the manacles at the Tower of London, and it's not like the docents at Mount Vernon are popping George Washington's dentures into their mouths and demonstrating how the former first president would have eaten corn on the cob.

But the Boulder-based Ars Nova Singers have absolutely no qualms when it comes to breathing life into old relics. In this case, the relic in question is a centuries-old motet written by English composer Thomas Tallis — a musical movement so complex and technical that it is rarely performed by a live choral group.

On Friday and Sunday, Ars Nova Singers will present its first concert of the new year, "Rebirth," featuring beloved masterpieces from Henry Purcell, William Byrd and Emilio de' Cavalieri. At the center of the program is Tallis' sweeping composition, "Spem in alium."

Led by Tom Morgan, artistic director and founder of Ars Nova, Boulder's nationally acclaimed, 40-piece vocal ensemble has long presented a capella music from the Renaissance and the 20th and 21st centuries — sometimes unearthing pieces so obscure that few living ears have been exposed to them.

As Ars Nova singer Andrea Weidemann puts it: "We're a group that's committed to being a museum for music."

Weidemann, a soprano, joined Ars Nova Singers in January of 2023, and is a member of the group's smaller, professional sub-group called the Ensemble Singers. While Wiedemann is a professional singer through and through, she also happens to be a bit of a history buff, and spent some time explaining the intricacies of "Spem in alium."

"What's unique about this piece, and why it is so groundbreaking, is that it was written for eight choirs, made up of five people each," Weidemann said. "Contemporarily, when we think of choral music, we think of it being sung by just one choir. However, with 'Spem in alium,' the music was written for eight separate ensembles to all get together and sing music for the birthday of someone in the nobility."

"Spem in alium" is usually performed with the singers arranged in a circular or horseshoe shape, creating the sensation that sound is traveling from one direction to another and then back again, completely immersing the listener in a lush, blooming euphony.

"It's kind of like the loudest thing that you can think of, especially for that time period," Weidemann said. "There weren't speakers or anything, so in the early 17th century, it's kind of described as like the very first surround-sound experience."

As Ars Nova has exactly 40 members, each member of the choir is in charge of a separate musical part, which is, understandably, extremely challenging to execute.

But if anyone can pull off a musical feat of this difficulty, it's the Ars Nova Singers.

"We are proud of having built an ensemble that can undertake works of this level of difficulty," said Morgan. "It requires a significant degree of independence on the part of the singers, and for some of the new music we undertake, it's really helpful to have several singers with perfect pitch."

While "Rebirth" will test out the Ars Nova Singers' vocal chops, it's also meant to gently usher audiences through the final weeks of winter. While the concert begins with music that was created in the Dark Ages, the rest of the evening will feature music made later in time — ending with Josef Rheinberger's Mass in E-flat major for double chorus, wrapping up the concert on a hopeful, spring-tinged note.

"We want people to know this concert is very contemplative in nature," said Weidemann. "It will be like a sound bath, something that's good for the spirit. And though maybe people may not understand the ins and outs and the complexities of it all, it's pretty easy to understand in terms of shapes and colors, if you just close your eyes, relax and listen."

Adding to this notion, Morgan said, "We are responsible for the vibrations we send into the world. It's my goal to show that some of this intricate, meticulously constructed music can also be heart-wrenchingly beautiful. The human voice can make this connection very directly."

Join Ars Nova Singers for "Rebirth" on at 7:30 p.m. Friday at Mountain View United Methodist Church, 355 Ponca Place, Boulder; and on at 2:30 p.m. Sunday at Central Presbyterian Church, 1660 N. Sherman St., Denver. Tickets are $10-$30. For more information and to purchase tickets, visit arsnovasingers.org.