The following Maple, Face Frame Crown style, white-painted entertainment system was put together using a combination of bookcases, a center entertainment console, and a bookcase bridge. Here is how this was put together to create a cascading wall unit with varying depths and heights.
The central piece is a CN4 entertainment console 84″W x 36″H x 24″D, painted white with raised-panel doors. It has deluxe base moulding that wraps around the sides and is mitered to meet the moulding on the adjacent units.
The piece above the TV is a BR2 bookcase bridge 84″W x 12″H x 16″D set above the other bookcases with deluxe crown moulding wrapped around each side.
The bookcases on each side are stepped back, with the first 16″D, then 14″D, then 12″D. They have deluxe crown moulding that is wrapped around to meet the bookcase next to it. The pieces next to the center have a mini-miter so that the crown moulding overlaps the face frame of the bookcase bridge. On the outer side, they have a partial wrap with a mitered cut to meet the moulding on the next piece. The next piece has an inside miter cut to meet that crown, and so forth. The result is a seamless flowing sequence of moulding that appears built-in and connected. In reality, these were ordered pre-built to fit the design.
Had the homeowner wanted to go all the way to the ceiling, we could have used base units with tall hutches, but since this is a very tall ceiling, it probably would have been overkill.
The diagram below was used to specify how everything would fit together.