In a dropped ceiling assembly system elements are provided which include an elongate planar shelf held below an elongate spine. The shelf has lateral edges which can support edges of a ceiling tile resting thereon. This spine is configured to be held in position either adjacent to spines of other elements within a dropped ceiling or from above, such as by suspension wires passing through suspension holes in the spine. A compartment is provided on an underside of the shelf which is sized and shaped to receive and hold at least a portion of a loudspeaker therein. The loudspeaker mounting system is thus integrated into the shelf which also acts to hold ceiling tiles within a dropped ceiling.