In music, a chorale prelude is a short liturgical composition for
organ using a
chorale tune as its basis. It was a predominant form of the German
Baroque era and reached its culmination in the works of
J.S. Bach, who wrote 46 (with a 47th
unfinished) examples of the form in his
Orgelbüchlein.The liturgical function of a chorale
prelude in the Baroque period is debated. One possibility is that they were used to introduce the hymn about to be sung by the congregation, usually in a
Protestant, and originally in a
Lutheran, church. Although it was typically a
polyphonic setting, the melody would be plainly audible. There was sometimes an
obbligato line above or below the melody.
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