Not to disuade you, but I would put serious thought into treating that room if you are going to enjoy it at loud volumes or want a discrete presentation for movie soundtracks.

Its a pile of work to do it right, but can be done.

We did a room ages ago with 13’ ceilings and did this:

[Linked Image from imgur.com]

[Linked Image from imgur.com]

[Linked Image from imgur.com]

[Linked Image from imgur.com]