Voice exchange
In music, especially Schenkerian analysis, a voice exchange (German:Stimmtausch; also called voice interchange) is the repetition of a contrapuntal passage with the voices' parts exchanged; for instance, the melody of one part appears in a second part and vice versa. It differs from invertible counterpoint in that there is no octave displacement; therefore it always involves some voice crossing. If scored for equal instruments or voices, it may be indistinguishable from a repeat, although because a repeat does not appear in any of the parts, it may make the music more interesting for the musicians. It is a characteristic feature of rounds, although not usually called such.