Bach, Johann Sebastian, 1685-1750. Choräle von verschiedener Art, BWV 645-650

Sechs Chorale von verschiedener Art: auf einer Orgel mit 2 Clavieren und Pedal vorzuspielen (lit. 'six chorales of diverse kinds, to be played on an organ with two manuals and pedal'), commonly known as the Schübler Chorales (German: Schübler-Choräle), BWV 645–650, is a set of chorale preludes composed by Johann Sebastian Bach. Johann Georg Schübler, after whom the collection came to be named, published it in 1747 or before August 1748, in Zella St. Blasii. At least five preludes of the compilation are transcribed from movements in Bach's church cantatas, mostly chorale cantatas he had composed around two decades earlier. The fact that Bach had gone to the trouble and expense of securing the services of a master engraver to produce a collection of note-for-note transcriptions of this kind indicates that he did not regard the Schübler Chorales as a minor piece of hack-work, but as a significant public statement. These six chorales provide an approachable version of the music of the cantatas through the more marketable medium of keyboard transcriptions. Virtually all Bach's cantatas were unpublished in his lifetime.