passacaglia
A compositional form based on a continuously repeated bass line or harmonic progression, typically in triple meter and slow tempo.
In Depth
The passacaglia originated as a Spanish dance form (from pasar — "to walk" and calle — "street") in the early 17th century before evolving into one of the most sophisticated variation forms in Western music. A short bass theme, usually four to eight bars long, repeats throughout the work while upper voices present increasingly elaborate variations. Unlike the related chaconne, which is built on a repeated chord progression, the passacaglia is defined by its bass melody. J.S. Bach's Passacaglia and Fugue in C minor (BWV 582) represents the form's apex, building twenty variations over a repeating bass theme into a towering structure of increasing complexity before dissolving into a double fugue. The form experienced a revival in the 20th century, with major examples by Brahms (Symphony No. 4 finale), Shostakovich, and Britten. The passacaglia's combination of repetitive foundation and free variation makes it a compelling metaphor for individual expression within constraint.
The finale of Brahms's Fourth Symphony is a monumental passacaglia with 30 variations on an eight-note theme borrowed from Bach's cantata Nach dir, Herr, verlanget mich.