Sonata in D major for piano duet, K.381

The Sonata in D major, like the one in B flat major, was part of the Salzburg repertoire of Mozart and his sister Nannerl. It is thought to have been written early in 1772 and, though it is scarcely more ambitious than the C major Sonata, K.19d, it does represent an advance on it in that it is more authentically classical in shape. There is in this case a clearly defined second subject (anticipating Voi che sapete at one point). Although the short development is not concerned with the main themes, the recapitulation is free enough to make more of their potential.

The G major Andante includes one of Mozart’s most engaging four-hand colour effects - the introduction of the second subject with the theme in both parts two octaves apart and broken chord accompaniment between. There is another delightful idea in the brief but witty development section of the Allegro molto, where the least significant aspect of the second subject finds itself the centre of attention.