Rather than the usual bombast or snooze-inducing "relaxation music," the U.K. six-piece known as Clean Bandit mash classical music and pop forms for an airy and dreamy yet driven sound that's like the chamber music version of house music. The group's four core members were known as the Chatto Quartet, a classically trained string quartet that performed J.S. Bach and cited Jacqueline du Pré as an influence, but their post-show, wind-down music often consisted of garage, 2-step, Craig David, and Arcade...