In musical parlance, the title of this work is an instruction to French horn players to raise the bell of their instrument. However, it is the surreal imagery of a literal rendering of the term that has inspired the composition of this piece. Pavillons en l'Air is a sequence of "floating" sound structures dissolving into one another, re-emerging and dissolving again. Two versions of the piece exist: the original for tuba and percussion and an alternative for double bass and percussion. In both versions the percussion and tape parts are identical, while the tuba and double bass parts differ considerably.

More often than not the tuba and double bass are stereotyped as sluggish, unpoetic, mainly support-role instruments. In Pavillons en l'Air, however, both instruments constantly explore their individual identity, in the case of the tuba with the use of multiple sonorities (singing and playing at the same time) and in the case of the double bass with the extensive use of an array of special effects (harmonics and other non-conventional sounds). They are pitted against high shakuhachi and Japanese percussion sounds in the tape part. The tape represents an idealized sound world which the live instruments try to reach and in so doing they are constantly engaged in pushing their upper register to the limit. Pavillons en l'Air is the first piece of a tetralogy of electroacoustic works entitled Quaternio, the others of which are The Birth of Venus, From the Vanishing Gardens of Eden and Of Threads and Labyrinths.