(Photo: Mary Reinholz)

Last night on the northern end of Union Square, passersby stopped and listened– some in rapt astonishment– to classical music, the kind they’d normally hear at Carnegie Hall. Except that these soulful sounds were coming from top performers playing in a popup theater that came out of back of an old U-Haul. The Music Haul is a tour bus operated by Yellow Barn, an international center for chamber music based in Putney, Vermont, that seeks to bring Beethoven, Bartok and Mozart to the masses.

We paused to catch “Oblique” music composed by Brooklyn percussionist Jason Treuting, who has played at venues as diverse as BAM and the Knitting Factory. He was joined by a quartet: violinists Ariana Kim and Max Tan; cellist Thomas Mesa and Margaret Dyer on the viola. Their set was one of the last on the final day of Music Haul’s nine-day debut tour of 80 stops in New York City, among them Smorgasburg in Williamsburg and, yes, outside of Carnegie Hall.

Seth Knopp, Yellow Barn’s artistic director, told us during a call to Vermont that more than 80 high-quality musicians had responded to his email asking for volunteers to donate their performances for the New York tour. “Many had been involved with our residential program and many were performing throughout the city,” he said. “We wanted to engage people in the moment and to (have them) experience music that’s committed and heartfelt.”

(Photo: Mary Reinholz)

Knopp noted in an email that the programming included a day dedicated to Bach’s cello suites and a Memorial Day performance of “Musicians Indivisible: Protest Mix Tape” with Broadway musicians; spoken word performances and Carnegie Hall’s Ensemble Connect; and even a new work inspired by Dick van Dyke’s one-man-band.

At left, drummer/composer Jason Treuting. (Photo: Mary Reinholz)

Massachusetts architect John Rossi of Visible Good reconfigured the old U-Haul that Yellow Barn had purchased. Knopp described the truck as a self-contained “traveling concert venue for as many as six musicians.” It has climate-controled passenger and storage areas and enough storage room for percussion, string instruments and even a piano.

Yellow Barn, a non-profit, wasn’t looking to raise money when it launched Music Haul in 2015– first in Vermont, then in Baltimore, followed by Dallas and Boston. “It’s mission-based– that’s why there are so many volunteers,” said Catherine Stephan, executive director of Yellow Barn. “There’s a heightened awareness that everyone needs to reconnect with community and to feel common ground. Musicians can communicate at a time when we’re driven by rhetoric and need to connect back to the ground water.”