Passacaglia

The passacaglia (/pæsəˈkɑːliə/; Italian: [pasːaˈkaʎːa]) is a musical form that originated in early seventeenth-century Spain and is still used today by composers. It is usually of a serious character and is often, but not always, based on a bass-ostinato and written in triple metre.

The term passacaglia (Spanish: pasacalle; French: passacaille; Italian: passacaglia, passacaglio, passagallo, passacagli, passacaglie) derives from the Spanish pasar (to walk) and calle (street). It originated in early 17th century Spain as a strummed interlude between instrumentally accompanied dances or songs. Despite the form's Spanish roots (confirmed by references in Spanish literature of the period), the first written examples of passacaglias are found in an Italian source dated 1606. These pieces, as well as others from Italian sources from the beginning of the century, are simple, brief sequences of chords outlining a cadential formula.

The passacaglia was redefined in the late 1620s by Italian composer Girolamo Frescobaldi, who transformed it into a series of continuous variations over a bass (which itself may be varied). Later composers adopted this model, and by the nineteenth century the word came to mean a series of variations over an ostinato pattern, usually of a serious character. A similar form, the chaconne, was also first developed by Frescobaldi. The two genres are closely related, but since "composers often used the terms chaconne and passacaglia indiscriminately [...] modern attempts to arrive at a clear distinction are arbitrary and historically unfounded". In early scholarship, attempts to formally differentiate between the historical chaconne and passacaglia were made, but researchers often came to opposite conclusions.

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