Bach’s glorious Magnificat, composed for his first Christmas in Leipzig, was designed to impress — its elaborate text painting and wide range of moods making it one of the most vivid works in Bach’s choral repertoire. So too, was his intricate motet for double choir, Singet dem Herrn, which Bach composed in Leipzig just a few years later. These choral masterpieces are matched here by the glittering orchestration and staggering virtuosity of his Suite in B minor and Brandenburg Concerto…