May 5. Strawbs stood apart from the rest of the early 1970s British prog rock movement in that their roots were in folk music, rather than classical or jazz à la their peers like Yes (whose Rock Wakeman was once a member). Founded by singer and guitarist Dave Cousins, the band began as bluegrass trio the Strawberry Hill Boys and recorded their eponymous 1968 debut with vocalist Sandy Denny, who soon left to join Fairport Convention. From there on out their albums became increasingly electrified and epic, an acknowledged fan favorite being the prog-tastically titled Hero and Heroine. And it's that entire 1974 opus that the full electric Strawbs will perform on this special night at the Towne Crier. (Alejandro Escovedo rocks May 12; Kathy Mattea croons May 13.) 7:30pm. $35. Beacon. (845) 855-1300.