If Sonata No. 11 was a closing, summarising chapter of Beethoven's early sonatas, then Sonata No. 12 is a door leading to exciting, hitherto unexplored musical worlds. Th structural innovation is easy to point out: out of the Sonata's four movements, none are in actual sonata form. Instead, Beethoven brings together a moderately slow opening movement (a theme with variations), a blazing scherzo, a funeral march and a quicksilver finale to form a fascinating story arc.
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