stretto

This overlapping, called stretto, is often found near the end of a fugue, as a means of building to a climax, but may occur anywhere, usually after the exposition. Examples from The Well-Tempered Clavier include Nos. 1 and 8 from Book 1 and Nos. 5, 7, and 22…

, by stretto (playing the theme against itself with repeated, closely spaced entrances) and augmentation and diminution (playing the theme in longer or shorter note values). Johann Sebastian Bach, master of the fugue, used the term ricercar for two pieces in The Musical Offering (1747).