피아노 소나타 30번 마장조 작품번호 109 (Piano Sonata no. 30 in E major, op. 109)

Ludwig van Beethoven's Piano Sonata No. 30 in E major, Op. 109, composed in 1820, is the third-to-last of his piano sonatas. In it, after the huge Hammerklavier Sonata, Op. 106, Beethoven returns to a smaller scale and a more intimate character. It is dedicated to Maximiliane Brentano, the daughter of Beethoven's long-standing friend Antonie Brentano, for whom Beethoven had already composed the short Piano Trio in B♭ major WoO 39 in 1812. Musically, the work is characterised by a free and original approach to the traditional sonata form. Its focus is the third movement, a set of variations that interpret its theme in a wide variety of individual ways.