The German musician, Johann Andreas Kuhnau (= JAK), was Kantor, nephew of Johann Kuhnau (1660-1722), who was the predecessor of J.S. Bach as Thomaskantor.
Johann Andreas Kuhnau attended the Thomasschule in Leipzig from 1718 to 1728, studied privately with J.S. Bach and was J.S. Bach main copyist in Leipzig from 1723 to 1728. In 1729 he was appointed Kantor at Grimma. Like other J.S. Bach pupils, he also acted as copyist. He was, in fact, one of J.S. Bach's principal copyists at Leipzig, and is perhaps the most reliable and productive copyist that J.S. Bach ever used. He was identified in the earlier J.S. Bach literature as Anonymous 3, or Hauptkopyst A.