As in the case of the 6 years later 'Waves', Rondo deals with the principle of ambiguity. It is for 6 players placed in a circle. Each musician has a collection of instruments including a cymbal and some drum. The first player has a high-pitch cymbal and drum, the second's instruments are lower pitched, an so on. The sixth man in fact plays on a deep tam-tam, which might be termed a "bass-cymbal", and on kettle drums. This chain of pitches is the frame for the work within which takes place the ambiguity between the spectrum of random 'noises' and attacks - indefinite rhythms almost like raindrops far and near - and well-defined tones where all players play deep tones together and in clear-cut beats.
The title 'Rondo' refers partly to the circle of instruments and partly to the musical form, where a motive keeps recurring through the piece. It is heard the first time played by the tube bells, and finally, pianissimo on the vibrahone.
Composed in 1964 and dedicated to Bent Lylloff.