Piano Sonata No. 13 in B‑Flat Major

As with Mozart’s other sonatas from this period, the Piano Sonata No. 13 was composed later than originally thought. It has now been dated to his stay in Linz on the return journey from Salzburg to Vienna in 1783, making it contemporaneous with his “Linz” Symphony, No. 36. Whereas some of Mozart’s piano sonatas emphasise thematic diversity and contrast, this sonata has a prevailing unity of mood and character and an economy of melodic material. The first movement, in a sunny B-flat major, is predominantly lyrical, with an alluring first theme built on a series of expressive appoggiaturas. Despite the graceful nature of much of the music, Mozart explores areas of greater turbulence and drama, such as the deflection into F minor in the development section, and even more so in the startlingly chromatic middle section of the slow movement, which twists from E-flat major into more remote harmonic regions. The rondo finale has the character of a concerto movement, with “solo” passages alternating with allusions of a full orchestra, complete with a full-blown cadenza toward the end.