Michelle Henkel, owner and teacher at the Whispering Cave in Wayzata, was accompanied by Minnesota Orchestra harpist Kathy Kienzle at a yoga class last month at Orchestra Hall in Minneapolis. (Marci Schmitt — Minnesota Orchestra/The Minnesota Star Tribune)

Sunlight streamed into Orchestra Hall's lobby, where I stood, right foot pressed against my thigh, arms stretched high and wide. Tree pose. My left leg shook a little. So I focused, instead, on the music.

This was no piped-in playlist. A harpist was gently plucking her grand instrument's strings just 10 feet in front of me.

The Minnesota Orchestra just began hosting yoga classes in its big, bright lobby, with musicians setting the mood. For the first class, on a Sunday morning in November, principal harp Kathy Kienzle, dressed in concert black, performed chill, ethereal tunes, including Debussy's classic "The Maid With the Flaxen Hair."

"I've never had a yoga class in my life," Kienzle admitted afterward.

She had asked a fellow harpist — who often performs at yoga classes — for tips. They weighed whether playing well-known pieces would be distracting or invigorating. In the end, Kienzle did a mix: "I used a lot of teaching pieces that have the right mood to them."

What worked: Attendees buzzed about the concept, chatting with one another as they rolled out their mats. We began by lying on those mats, which came with this warning: "Don't hit your head; the floor's really hard." The room was a tad cold, too.

But the sound was perfect: Throughout the class, the instructor, wearing a wireless microphone, could be heard clearly alongside the harp, never overpowering it.

Once the class picked up momentum, music and movement synchronized to create some beautiful moments. At one point, we rose into crescent lunge, swinging our arms back behind us into the "airplane" version of the pose. Meanwhile, Kienzle played a minimalist, meditative John Cage piece titled "In the Landscape." We reached our arms back farther, higher.

"It's almost like you're going to take flight," the instructor told us. "You can feel that lift."

The harp rose too, its arpeggios floating higher and higher.

The back story: The idea for this mashup sprang from a marriage between a yogi and a musician. At a conference a few years back, Holly Slocum, a yoga instructor and wife of a now-retired orchestra librarian, heard that the Luxembourg symphony was putting on yoga classes.

"And I thought, 'We need to do this here,' " said Slocum, who teaches at Good Vibrations Yoga in Hopkins.

The details: Each class will pair a different musician and a different yoga instructor, so the vibe will vary. The hourlong classes cost $35, plus taxes and fees. Which is pretty pricey for a yoga class but cheap for an intimate performance. The first class' 100 slots quickly sold out.

Up next: The Minnesota Orchestra has two more yoga classes on its calendar. On Feb. 10, violinist David Brubaker will score the sun salutations, and the March 24 class features flutist Adam Kuenzel.

Jenna Ross • 612-673-7168