The 9540 is a stand-alone 40 x 20 video switcher in three rack units. One or more 9540 video switchers can be combined with 9541 audio switchers to provide a maximum of 7 switching levels.
Typical configurations:

One 9540 and one 9541 switcher providing a complete 40 x 20 video and dual audio system
Two 9540 switchers with one 9541 switcher producing a 40 x 40 video and mono audio system
Three 9540 switchers and one 9541 switcher forms a 40 x 20 RGB and dual audio system
A redundant power supply is optionally available.

The 9541 is a stand-alone 40 x 20 dual audio or 40 x 40 mono audio/time code switcher in four rack units. One or more 9541 audio switchers can be combined with 9540 video switchers to provide a maximum of 7 switching levels.
Typical configurations:

One 9540 and one 9541 switcher providing a complete 40 x 20 video and dual audio system
Two 9540 switchers with one 9541 switcher producing a 40 x 40 video and mono audio system
Three 9540 switchers and one 9541 switcher forms a 40 x 20 RGB and dual audio system
A redundant power supply are optionally available.