Symphony No.94 in G major, Hob. I:94 "Surprise Symphony"

Haydn's music contains many jokes, and the Surprise Symphony includes probably the most famous of all: a sudden fortissimo chord at the end of the otherwise piano opening theme in the variation-form second movement. The music then returns to its original quiet dynamic, as if nothing had happened, and the ensuing variations do not repeat the joke. (In German it is commonly referred to as the Symphony "mit dem Paukenschlag"—"with the kettledrum stroke").