Piano Concertos K. 107 (Mozart) that publication). Therefore, when these works are enumerated with the rest, it can be seen that Mozart composed 30 keyboard concerti. These three works, however, and the concerti numbered as Piano Concertos 1 through 4 are actually not original compositions, but arrangements of works by other composers. Piano Concertos K. 107 (Mozart) The Piano Concertos, K. 107 are three keyboard concertos by Wolfgang Amadeus Mozart, based on sonatas by Johann Christian Bach. These sonatas are from J.C. Bach's Op. 5; Mozart turned Sonata No. 2 in D, Sonata No. 3 in G, and Sonata No. 4 in E from this
Wolfgang Amadeus Mozart listeners and performers. These developments were not witnessed by Mozart's father, who had died on 28 May 1787. In December 1787, Mozart finally obtained a steady post under aristocratic patronage. Emperor Joseph II appointed him as his "chamber composer", a post that had fallen vacant the previous month on the death of Gluck. It was a part-time appointment, paying just 800 florins per year, and required Mozart only to compose dances for the annual balls in the Redoutensaal (see "Mozart and dance"). This modest income became important to Mozart when hard times arrived. Court records show that Joseph's aim was