An audio-video (AV) system in one embodiment includes a mounting apparatus for mounting the system to a wall support located behind a wall surface and within an in-wall space. The mounting apparatus includes a support member for supporting at least one component in a support space within the in-wall space, a display mounting member 30 for mounting a display device, and a removable wall opening cover for concealing at least a portion of the in-wall space that would otherwise be visible through a wall opening to a viewer. Various multimedia-supportive devices, including loudspeakers and a subwoofer, may be concealed behind the cover in the in-wall space.