The concerti grossi, "Brandenburg Concertos", composed by J. S. Bach, were unusual in their use of viola. The third concerto grosso, scored for three violins, three violas, and lower strings with basso continuo, requires occasional virtuosity from the violists. The sixth concerto grosso, Brandenburg Concerto No. 6, which was scored for 2 violas "concertino", cello, 2 violas da gamba, and continuo, had the two violas playing the primary melodic role. He also used this unusual ensemble in his cantata, Gleichwie der Regen und Schnee vom Himmel fällt, BWV 18 and in Mein Herze schwimmt im Blut, BWV 199, the chorale is accompanied by an obbligato viola.