This Labor Day holiday weekend, Sunday Baroque is featuring some of the hardest working musicians of the 16th through 18th centuries: exceptionally prolific composers including German musician Michael Praetorius who wrote more than 1500 compositions … and Neapolitan keyboard virtuoso Domenico Scarlatti, who created 555 keyboard sonatas. They’ll do the work while you enjoy the holiday weekend on Sunday Baroque, starting at 7 a.m. on 91.1, 107.5 and wshu.org, and at 10 a.m. on 89.9.