sonata-allegro form

Sonata form is a musical form that has been used widely since the early Classical period. It has typically been used in the first movement of multimovement pieces, and is therefore more specifically referred to as sonata-allegro form or first-movement form.Sonata form was traditionally seen as a way of organizing the musical ideas in a movement on the basis of key. While not described and named until the early 19th century, the form derived from the binary form used by 18th century early Classical composers such as Johann Stamitz, Carl Philipp Emanuel Bach, and Johann Christian Bach, and came into common usage in the works of later composers of the period, most notably Joseph Haydn and Wolfgang Amadeus Mozart.
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