Where the #@*% are the small AV Receivers?

I recently moved into a new home. In the family room is an existing feature-wall-built-in that is wired for 7 channel (channels 6 and 7 being for front height) sound. The built-in includes an electric fireplace, a spot for a flatscreen TV above, which can be shuttered with some clunky doors. On either side of the fireplace are low-doored cabinets with three shelves above. It’s a beautiful unit and is altogether pretty awesome until the home theater geek in me took a closer look.