A passacaglia is a form of ground bass in triple time, and can be found in the works of Bach, Buxtehude, and also in the symphonies of Brahms, Shostakovich and Vaughan Williams.
This particular work dates from (we think) 1713. It is in two parts – a set of variations on the Passacaglia theme, and then a double fugue on the same.
As with a number of Bach works, scholars find hidden meaning and clues in his works. In the case of this work the organist and scholar Marie-Claire Alain has found chorale melodies hidden:
- Bars 8-12 has Nun komm’ der Heiden Heiland in the top part
- Bars 24-28 has Von Gott will ich nicht lassen
- Bars 49-72 has Von Himmel jam der Engel Schar (in the scales)
- Bars 72-96 has Herr Christ, der Ein’ge Gottes-Sohn
- Bars 96-120 has Christ lag in Todesbanden in an ornamented figure moving from soprano to alto to bass
- Bars 144-168 has part of Estanden ist der heil’ge Christ.
She also adds that there are 21 repetitions of the ground bass, and then 12 fugal statements – this sort of number play is typical of Bach.
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