A 21st century folk music orchestra featuring a rotating cast of some of the brightest names in jazz, bluegrass, classical, and world music, pianist/accordionist/composer Sam Reider’s genre-bending acoustic ensemble quickly became an audience favorite in its first appearances here. Intensely melodic, often wildly exuberant and always dizzyingly virtuosic, their performances have been called “a mashup of the Klezmatics, Quintette du Hot Club de France, and the Punch Brothers.”