About this work
Mozart's musically gifted sister, Nannerl, figured prominently in several of his compositions. Some accounts insist she was at least as gifted a keyboard performer as her younger brother, and as early as 1764, when Wolfgang was eight and Nannerl was thirteen, they toured and performed together at either one or two keyboard instruments. Thus, several years later, the idea of a concerto for two pianos likely came naturally to Wolfgang. No specific circumstances of this work's creation have been unearthed, however.
In 1779, the young composer had thrashed his way through the shoals and pitfalls of adolescence and endured his first heartbreak. After an extended tour of Europe, he reluctantly accepted the forgiveness and employ of the Archbishop of Salzburg and although the man was a Philistine when it came to music, Wolfgang set about trying to please him. With both the French and Italian styles still fresh in his mind, he set down two fine works in the double concerto format. The second of these was the Sinfonia Concertante for Violin and Viola in E flat, K.364 and the first was the present piece. While there is some evidence that fragments of the work were set down as early as 1775, the piece is generally considered to have been finally assembled and finished in early 1779.
In three movements, and relatively long at 25 minutes, the work is challenging for both soloists. The parts are also equally assigned so that there is not a first solo and a second solo. Passages intermingle, and the piece in general is a tour de force for performers and listeners alike. The first movement, a ten-minute Allegro, opens with a lengthy orchestral introduction containing an ambitious theme. Both pianos finally enter together, and after briefly alternating introductory phrases, join together in the first theme. A second theme is more ominous, and sounds as if it could be the basis for early silent film dramatic accompaniment. The orchestra puts a stop to this with a repeat of the brusque opening; after a gentle recapitulation, the movement ends in a tripping double cadenza and coda.
The second movement, an eight-minute Andante, begins as a stately Minuet in the orchestra. When the theme appears in the pianos, it is divided into two solo passages. The two soon seem to flow together, and passages alternate between soloists and orchestra, nicely leading and accompanying each other. The movement also offers one of the mature Mozart's first uses of surprise dissonance, as unexpected notes appear in exposed piano passages. The movement ends abruptly. The finale is a marvelous rondo. Although it is appropriately scored for the instruments and orchestra of his day, the size and power of it make one wonder what Mozart might have crafted with modern concert grand pianos at his disposal.
The genius of the work lies in its seamlessness. Even the casual listener will discern that there are too many notes to be played by a single instrument, yet without visual reinforcement it is essentially impossible for the hearer to separate the solo parts. Mozart created here a large work for four perfectly coordinated hands and two full-size keyboards. It is significant in his output as standing among the first works of his maturity following his return to Salzburg and the death of his mother.