In his later years Beethoven, like many other composers, turned to the music of J. S. Bach for new ideas. However, Beethoven's admiration of the late Baroque master began while he was still in Bonn. Possibly as an homage to Bach's preludes and fugues in every key, Beethoven composed two Preludes, both employing each of the 12 major keys. These are less successful works than his later contrapuntal masterpieces, such as the Piano Sonata No. 28, Op. 101, the first movement of the String Quartet, Op. 131, and the Grosse Fuge, Op. 133. It is possible that Beethoven wrote the Preludes, Op. 39, as composition exercises for his teacher, Christian Gottlob Neefe (1748-1798). The Preludes were published in 1803 by Hoffmeister and Kühnel in Leipzig.