The Piano Sonata in A minor D.845 (Op.42) by Franz Schubert is a sonata for solo piano. Composed in May 1825 and entitled Premiere Grande Sonata, it is the first of three sonatas published during the composer's lifetime, the others being D.850 and D.894. Conceived as a set, these works were composed during what was reportedly a period of relatively good health and spirits for Schubert, and are praised for their quality and ambition. This first sonata in particular marks a significant step toward the composer’s mature piano sonata style; the format and several characteristic stylistic elements continue through the last.
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