Rhiannon Giddens has traveled the world playing American music. Born in North Carolina, she has sung, played violin, and plucked banjo in her band, the Carolina Chocolate Drops. She has also worked as a solo artist, performing traditional folk, country, blues, and bluegrass, including original compositions. Both a Grammy winner and a recipient of the MacArthur Fellowship “Genius Grant,” Giddens is performing two sets at this weekend’s Fresh Grass festival at MASS MoCA in North Adams, Massachusetts. While her Saturday performance will be a more conventional set, Giddens tells WAMC her Friday set that opens the festival will be unique.