Composer, born in Rohrau, Austria. Educated at the Cathedral Choir School of St Stephen's, Vienna, he earned his living initially by playing in street orchestras and teaching. He became musical director (1759--60) for Count von Morzin's court musicians, for whom he wrote his earliest symphonies. He entered the service of the Esterházy family as musical director in 1761, staying with them until 1790. He was given great scope for composition, and among his innovations were the four-movement string quartet and the "classical' symphony. His output was vast, and he earned a major international reputation. His works include 104 symphonies, about 50 concertos, 84 string quartets, 24 stage works, 12 Masses, orchestral divertimenti, keyboard sonatas, and diverse chamber, choral, instrumental, and vocal pieces.