During the late-eighteenth century, a number of different aria types emerged in Italian opera seria in conjunction with the establishment of the Classical style. One emergent aria form was the two-part, two-tempo rondo aria which first appeared in the 1760s and became standardized in the early 1780s. In its most conventional form, the rondo aria exhibited a two-tempo framework that includes an andante section followed by an allegro part. The andante most typically is constructed in a ternary fashion; the allegro likely contains gavotte rhythms. Examples of the rondo aria form can be found in Mozart's late operas and concert arias, as well as in the works of his Italian contemporaries, such as Giuseppe Sarti. Through various modifications, such as the introduction of pertichini, and the addition of a tempo di mezzo, the rondo aria nucleus was expanded to encompass a continued preference for dynamic expression. This rondo aria is the direct ancestor of the cantabile-cabaletta convention highly evident in Italian opera of the mid-nineteenth century.
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