Audio Systems: How to help sound proof future media room, wood frame walls, acoustic doors

Question
We are in the process of remodeling our entire home. We want to use a 20' long by 14' wide 10' high room for our theater room. The room is wood frame walls, ceilings and will be cover with drywall and insulation. We are running electric and audio cables now. Is there any design method we can incorporate now to help deaden sound transfer to our other rooms. What is the most bang for the buck soundproofing method used?

Answer
Great question.  By far, this is where I make the most clients as a consultant/designer.

Bar-none, the best money will be spent building a second set of walls.  You'll need a second set of wood frames for the walls - if any part of the inside walls touches the outside walls adjoining other rooms then acoustic energy (especially low-frequency rumbles) will transmit right on through.

If the rooms above and below are also important, you need to float a floor and hang a flase ceiling on resilient hangars.

Any pentrations (electrical/switch boxes, water pipes, wire poke-throughs) into the room also need to be sealed with a non-hardening caulk.

Doors should be solid core at the very least, with drop-in thresholds.  There are special-purpose acoustic doors that can be purchased with all the elements on place.

Any airconditioning ducts should be lined with 1' thick batting, and you should avoid a situation where a duct venting into your theater room also vents into rooms next door.

If all this sounds like allot, it is.  I have had some luck using resilient hangers on the inside of a single wood frame and using double sheetrock or, better yet, 3/4" ply-wood and sheetrock as a material for ceilings and walls.
You can also lay down soem sort of sprung-floor foam or foot-fall underflooring, then a layer of cement board, and then your flooring material to get some level of isolation from the floor below.

There is some scientific evidence to say that we humans a a little more tolerant of occasional or irregular low-frequency rumbles than, say, a contstant high-pitched whine, so if you are able to at least shore up the room against transmission of frequencies above about 100 Hz you might not even really notice.

I am happy to recommend specific products if you need to.  If you post a follow-up or a new question and check the "Private" box I might be more willing to share specific or personal information...