How often is someone using the master bath when you are in the theater? I would just wrap it with something to take the edge off the sound and call it a day. It's tucked in the closet and that should be your first line of defense.
If you box it in it will take up some head room getting to the back of your rack.
I had a similar situation to your's. I framed the pipe, filled with insulation, plywooded over the framing then double drywalled with 2 layers of GG. My clean out was left exposed for now, but eventually will get a double MDF/GG cover that will be secured by bolts and T nuts (for future access).
How often is someone using the master bath when you are in the theater?
Quite frequently as it turns out. After I put the daughter to bed I frequently head downstairs to watch some TV and the wife heads for her bathroom. When we built this house, we put in a large mater bath complete with jetted tub and a flat panel over it. Needless to say, she uses it a lot. When that tub drains, there is a major rush of water coming down those pipes.
Originally Posted by BIGmouthinDC
It's tucked in the closet and that should be your first line of defense.
Yes, but unfortunately, it is right there next to my rack which does not have a door and it is just feet from my seating area.
Before drywall you could follow the water flow across the theater room as the drain comes down the outside wall, goes across the theater ceiling, curves along the edge of the game room and then down the pipe in the closet. I managed to insulate the parts in the ceiling but once it hits that closet... well let's just say you fell like you are in the now famous Nautical themed theater also posted in here.
Good point on the clean out. I will have to come up with a removable door but I think I will box it in. I will probably just deal with it come spring so I don't have to be cutting inside.