Mozart - Piano Quartet In G Minor K. 478

When Mozart wrote this music in 1785,  quartets consisting of a violin, viola, cello and piano were somewhat of a novelty. Mozart was the first major composer to write for this combination of instruments. The music publishers of the time were always looking for new music to print for the amateur market, and a publisher in Vienna commissioned Mozart to write 3 (possibly more) piano quartets. The publisher printed the first piano quartet in G minor, but due to poor sales the publisher canceled his commission for the rest. The reason for the poor sales was that the music was too difficult for amateurs to play, and was no less difficult for listeners to be able to understand and appreciate.

The list of Mozart's compositions in a minor key is short. Two piano sonatas, one string quartet, two piano concertos, two symphonies, a string quintet and the piano quartet are works in a minor key. And of these nine works, four are in the key of G minor, Mozart's dramatic key.

The Piano Quartet in G minor is in 3 movements:

I. Allegro - Mozart begins the movement straight away with the first theme stated in unison by all 4 instruments:

The piano answers the initial statement. Once again all 4 instruments in unison play the statement, this time in a different key. The music proceeds with changes to a major key while echos of the theme are played in accompaniment. The piano gives voice to the second theme, the violin answers with its own material. After more transitional material, the exposition is repeated.  The development section begins with material related to previously heard music and weaves it into an intricate contrapuntal discussion between the instruments. The first theme is heard in a major key and the music transitions into differing keys, and after an extended development section the recapitulation begins. The music makes the obligatory key changes to the second theme as the music moves towards the coda. The opening theme is heard once again and is transformed to a dramatic end to the movement.

II. Andante - The middle movement is in marked contrast to the dark drama of the first movement as the instruments take turns in this gentle music in B-flat major, the relative major of the home key of G minor.

III. Rondeau -  In an even deeper contrast to the first movement is this music in the key of G major. The piano opens the movement with the rondo theme, all join in the second statement of the theme. The strings alternate with the piano throughout this movement, with all 4 instruments coming together to add some spice to it occasionally. Mozart adds variety by dipping into a minor key in a few places, but the music doesn't stay there long. The opening theme of the movement comes back one last time, and Mozart wraps up the quartet with a short coda.