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Jan Václav Hugo Voříšek (Johann Hugo Worzischek, 11 May 1791, Vamberk, Bohemia – 19 November 1825, Vienna, Austria) was a Bohemian composer, pianist and organist.
6 Impromptus Op. 7 (1816-1820?)
1. Allegro in C major
2. Allegro moderato in G major
3. Allegretto in D major
4. Allegretto in A major
5. Allegretto in E major
6. Allegretto in B major
The first recorded use of impromptu as a musical term occurred in 1817, in the Allgemeine musikalische Zeitung, an idea of the publisher to describe a piano piece by Voříšek . His Impromptus Op.7 were published in 1822, pieces known to his friend Schubert who subsequently used the description for several sets of music for piano, as did Chopin and numerous lesser composers.
In 1823-24, like Schubert, he was one of the 50 composers to contribute a variation on the same waltz by Anton Diabelli for the Vaterländischer Künstlerverein on which Beethoven composed his 33 variations (Op. 120).