The influence of J C Bach on Mozartwas significant. The two had met in London in 1764, when Mozart was still aboy. In 1772, Mozart created his first three piano concertos by rearrangingthree of J C Bach's sonatas. Beyond the concerto structure, the detail ofMozart's music suggests Bach's influence. His subtle ornamentation and cleveruse of suspensions and ambiguities of tonality also characterises J C Bach'swork.
Mozart's use of keys isparticularly innovative: in the first movement of the A major Piano ConcertoK488, the development section incorporates a passage of dialogue between thewinds and a larger grouping of piano and strings, modulating through E minor atbar 156, C major at bar 160, A minor at bar 164 and then through F major at bar166 to D minor at bar 168. The more obvious, related tonalities for a work in Amajor would be D and E major, the subdominant and dominant keys, and F# minor,the relative minor key. This type of harmonic device gives a strong sense ofdeparture from the safety and stability of the home key, making its eventualreturn in the recapitulation stronger and more satisfying.
This passage also shows examples ofMozart's innovative orchestration: the small group-large group contrast ofearlier concertos becomes a three-way interchange, with piano, winds andstrings forming three groups which are united and contrasted in a range ofcombinations. Conclusion
Mozart's innovations took thekeyboard concerto to a new level, and give some...