Ludwig van Beethoven's Piano Sonata No. 28 in A major, Op. 101, was written in 1816 and was dedicated to the pianist Baroness Dorothea Ertmann, née Graumen. This sonata marks the beginning of what is generally regarded as Beethoven's final period, where the forms are more complex, ideas more wide-ranging, textures more polyphonic, and the treatment of the themes and motifs even more sophisticated than before. Op. 101 well exemplified this new style, and Beethoven exploits the newly expanded keyboard compass of the day.
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