Concerto for Two Violins in D minor, BWV 1043

The Double Violin Concerto is usually dated to Bach's Köthen years, when he had a good court orchestra and no church obligations, although some scholars place it in the Leipzig 1730s instead; he later arranged it for two harpsichords in C minor as BWV 1062. The outer movements are strict fugal writing shared between the soloists, but the Largo ma non tanto is what carries the work: the two violins exchange a single melodic line in canon, each entering while the other is still finishing, so that the phrase never lands cleanly.