As part of the ongoing CSO From Home series, here’s the first movement of J.S. Bach’s third Brandenburg concerto, performed by Chicago Symphony Orchestra violins Yuan-Qing Yu, Gina DiBello and Simon Michal; violas Weijing Wang, Wei-Ting Kuo and Catherine Brubaker; cellos Kenneth Olsen, Karen Basrak and David Sanders, and bass Robert Kassinger.