Overture in the French style, BWV 831

The Overture in the French style, BWV 831, original title Ouvertüre nach Französischer Art, also known as the French Overture and published as the second half of Clavier-Übung II in 1735 (paired with the Italian Concerto), is a suite in B minor for two-manual harpsichord written by Johann Sebastian Bach. An earlier version of this work exists, in the key of C minor (BWV 831a); the work was transposed into B minor to complete the cycle of tonalities in Parts One and Two of the Clavier-Übung. The keys of the six Partitas (B-flat major, C minor, A minor, D major, G major, E minor) form a sequence of intervals going up and then down by increasing amounts: a second up (B-flat to C), a third down (C to A), a fourth up (A to D), a fifth down (D to G), and finally a sixth up (G to E). The key sequence continues into Clavier-Übung II (1735) with two larger works: the Italian Concerto, a seventh down (E to F), and the French Overture, an augmented fourth up (F to B-natural). Thus this sequence of customary tonalities for 18th-century keyboard compositions is complete, extending from the first letter of his name (Bach's "home" key, B-flat, in German is B) to the last letter of his name (B-natural in German is H).

The term overture refers to the fact that this suite starts with an overture movement, and was a common generic name for French suites (his orchestral suites were similarly named). This "overture" movement replaces the allemande found in Bach's other keyboard suites. Also, there are optional dance movements both before and after the Sarabande. Optional movements usually occur only after the sarabande. All three of the optional dance movements are presented in pairs, with the first one repeated (without internal repeats) after the second. Also unusual is the inclusion of an extra movement after the Gigue. This is an "echo", a piece meant to exploit the terraced loud and soft dynamics of the two-manual harpsichord. Other movements also have dynamic indications (piano and forte), which are not often found in keyboard suites of the Baroque period. With eleven movements, the French Overture is the longest keyboard suite ever composed by Bach. It usually has a duration of 30 minutes if all the repeats in every movement are taken.

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