The "Six Three-Part Preludes and Fugues" are regarded as a unique testimony to Mozart's profound interest in the works of Bach. Or was it a brilliant contemporary of his who arranged the two preludes and five fugues by Johann Sebastian, and one fugue by Wilhelm Friedemann for string trio and supplemented the collection with further preludes? The new editions put the music text of Johann Nepomuk David's edition of the parts to the test, especially the editor's practical arrangement, which reflect...