A couple of weeks ago, Cantus Vocal Ensemble, an all-male a cappella group based in Minneapolis, performed an eclectic mix of classical, spiritual and rock songs for a captive audience at Andover High School.

Simeon Toronto, a senior at the school and the president of its concert choir, said it made an impression on him and many other young singers in the audience. "We were just amazed. We were all blown away by the talent and performance," he said.

The singers are the "rock stars of the choir world," he said. "I look up to these guys. They're about as good as you can get in professional vocal performance."

The concert marked the start of the ensemble's yearlong residency at the high school. Every year, Cantus picks several high schools representing urban, suburban and rural areas to take part in its residency program, according to Shahzore Shah, a tenor with the group who doubles as its outreach education coordinator.

This year, that also includes South High School in Minneapolis and St. Michael-Albertville High School. The residency involves several master classes led by Cantus at each school, along with a winter festival that blends the choirs together. It culminates with a mass concert on May 17, he said.

So, throughout the year, schools get individual attention, but they also collaborate on pieces, he said.

That brings out a greater diversity of voices, he said, adding, "We want the three schools to benefit from each other and from working with us."

Cantus developed the program, which is in its sixth year, as a way to deepen its presence in the community, Shah said.

More broadly, the program, which is accepting applications for next year through Nov. 1, underscores the importance of music education, especially in light of budget cuts that often affect the arts, he said.

The residency

At the ensemble's prompting, Andover High School underwent a rigorous application process to land the residency, according to school choir director Melanie Kjellberg.

Besides submitting a recent recording of the concert choir as a sort of audition tape, the school gathered letters of support from students, parents and administrators, she said.

Kjellberg said the 68-member concert choir, which includes a mix of students in grades 10 through 12, has plenty to gain from the experience.

For starters, Cantus, a nine-member group that grew out of a venture at St. Olaf College in 1995, is unique in that it doesn't have a conductor, she said. As such, each vocalist takes turns leading the group.

"Getting to see that kind of collaboration, that's huge for the students," she said.

During the residency, Cantus will work to finesse various aspects of the choir's performance. It could be breathing technique, musical interpretation or tone production, depending on "what's important to our choir."

In general, it's about "making the music come off the page. Having great models for that is important," she said.

Cantus is also taking the time to talk to the students about the practical realities of being a professional musician. For example, following the opening concert, Cantus fielded questions about "how to live that life not only as a hobby, but as a career," she said.

Ultimately, she hopes that the students develop a better appreciation for music, "which is what makes us whole," she said.

Even though the residency is just ramping up, "The kids are just giddy about it. They understand that it means more from them. They feel very honored to be selected," she said.

Teaching good technique

As a part of the residency, Cantus will provide complimentary tickets for students and teachers to the occasional concert or rehearsal, "so they know what we're about and what we do," he said.

Shah explained that Cantus emphasizes the principles of "good, healthy singing," not one particular music genre or style. "By having good singing technique, you can make an operatic piece sound like an operatic piece and a pop piece sound like a pop piece," he said.

Besides the technical side of things, Cantus helps choirs gain the confidence they need to recruit more singers, especially males. "It's always a challenge for directors, generating more long-term interest in singing for students and support for the music program," he said.

The group wants to make it a banner year for the choir, which is preparing for upcoming singing engagements at Concordia College in Moorhead and at Carnegie Hall in New York City in early 2014, he said.

Senior Anna Wagner, vice president of the Andover concert choir, helped apply for the residency. She's looking forward to the group's master classes.

"We want to bring the music alive and take away as much from it as we can," she said.

Also, it's "cool to connect with other choirs in the state and hear what they're doing," she said.

Talking to the Cantus singers backstage at the school's private concert, she found "they're down-to-earth and funny guys and they were excited to be here."

"It wasn't just an obligation," she said. "They were listening and attentive."

Anna Pratt is a Twin Cities freelance writer.