A quarter century ago, the superstar classical cellist Yo-Yo Ma founded the Silkroad Ensemble, raring to tear down the walls that divide the likes of him from “world musicians” of a more improvisatory, vernacular bent. Through the encounters he orchestrated, mainstream Western audiences got to know sounds and styles heard across the centuries along the ancient trade routes between Europe and the Far East. The American folk musician and ethnomusicologist Rhiannon Giddens grew up under different skies but practices “world music” in an identical spirit. For Silkroad’s Silver Jubilee, Ma and Giddens share the stage—he on one (or more) of his priceless cellos, she on banjo, viola, and vocals. Other standard-issue “European” instruments like clarinet, violin, and bass contribute to the tapestry, as well. But they’re seriously outnumbered by “folk” and/or “exotic” instruments like the tabla, Celtic harp, pipa, accordion, and shakuhachi. Plus, of course, percussion—which, like the singing voice, belongs to humankind everywhere. —Matthew Gurewitsch