Movement 1: Allegro
Movement 2: Andante
Movement 3: Menuetto in canone – Trio al rovescio
Movement 4: Allegro
The opening Allegro is dominated by the various strands of its sombre opening theme. At the climax of the brief development Mozart takes a beseeching falling sequence originally heard on the three lower instruments and works it in searing contrapuntal imitation. As was Mozart’s wont in his minor-keyed compositions (in contrast to Haydn and Beethoven), the recapitulation cleaves to the minor throughout. The recasting and intensification of the lyrical E flat second subject when it returns in C minor is one of the most moving strokes in the work.
While the gently lilting Andante, in E flat, has a mellifluous, serenading charm (an unmissable foretaste here of the serenade in the same key in Così fan tutte), the minuet refutes its serenade origins with a truculent display of canonic ingenuity. At the opening the cello imitates the first violin at a bar’s distance, with the other instruments in support, making for some abrasive harmonic clashes. In the second half Mozart briefly enriches the contrapuntal weave with a three-part canon initiated by the violas. The Elysian C major trio is even more intricately fashioned, as a ‘double mirror canon’ for four instruments (the second viola is silent), in which the melodic line traced by the upper part of each pair is turned upside down by the answering lower instrument: ‘the visual image of two swans reflected in still water’, in the memorable words of Mozart scholar Erik Smith.
As in the C minor Piano Concerto, K491, Mozart writes a finale in the form of a square, compact theme and eight variations, many of which treat the theme quite freely. After the martial fourth variation, the fifth, initiated softly by violas (horns in the original version), expands the music’s scale and turns for the first time to a contrasting key, E flat major. Freest of all the variations is the seventh, a mysteriously chromatic meditation on the theme’s essence. Then, as the music seems to atomize, Mozart plunges into C major for a jolly send-off, and a belated reminder of the work’s alfresco serenade origins.
from notes by Richard Wigmore © 2010