I'm just a programmer, but I've been asked to help design a theater which needs to include some sort of acoustical wall treatment to soundproof the room as much as possible (it's a theater with bedrooms above it).

Is there a good online tool or documentation about the subject as a whole. I don't want to get too bogged down in "this one" vs. "that one" and i'm not sales/marketing but need to help engineer a solution with no understanding of the products I should use, time is should take, who does the work etc. If anybody can help shed a little light, I would greatly appreciate it.

RobZ

PS: we are located in Seacoast NH...just in case you are familiar with companies in this neck of the woods that do this sort of work

We are currently doing a custom install in a house on the lower of four (yes, four!) floors. The builder has used 40mm SoundChek panelling for the walls along with rubber insulated batons/furring channel to stick it to. We are yet to fire this puppy up but expect that theatre sound will be pretty quiet outside and vice-versa.
SoundChek is a proprietary plasterboard specifically designed for this.

See: [Link: infolink.com.au]

I am, however, in Australia, but I'm sure you guys over there would have many similar products available.

It will take a lot more than just wall treatment to isolate the theater, their will also be some construction involved. The cheapest way I've found is from this company:

http://www.quietsolution.com/

Acoustical wall treatments hanging on the wall inside the home theater won't neccesarily do much to prevent sound from leaking out into other areas of the home.

Another place to check out is [Link: kineticsnoise.com]

Towards the bottom of the Kinetics web page there are a couple of articles on "Isolating the Room" and "Treating the Interior"......might help shed some light on what is involved.

Some companies (Kinetics, Auralex, that I know of) will help you put together a design for the room (geared around their products of course ;-) ).

RobZ
Check out this:

www.QuietSolution.com

They have some white papers titled "Making Walls Quiet"... a great piece of info...

There is at least one word you really ought to avoid at this level of involvement: sound proof.

Your goal is acoustic isolation and separation. You want to minimize the amount of sound leaving the theater, and entering the theater from the outside (drain pipes, HVAC ducts, footfalls from rooms above, etc.).

There are certain basic construction tactics you can advise, but to provide any sort of guarantee (even one implied by providing "sound-proofing" materials), you really should enlist the assistance of an acoustical engineer specializing in this area.

On-wall acoustical treatments may be used to enhance the sound of a room, or as Floyd Toole puts it, for "sound field management."

It's nice to want to help out, but not advisable to make a promise that can't be met.

I nominate this for the best advice of the day.

Be sure the client's expectations are reasonable... the phrase "sound proof" is somewhere between misleading & dangerous, and will be impossible to accomplish unless professionally designed and executed.

Usually a minimum of sound transmission will require a maximum of cash extraction, and will still only work well IF the acoustical design is correct AND followed exactly.

If "sound proofing" is your goal (and your client's expectation) you'll need to float the floor walls and ceiling. Drywall both sides of both walls and leave a 6 inch gap. I would use two layers of drywall with tar paper (like for roofing) between them, it's much cheaper than the Auralex stuff. I would also use mineral fiber, the stiff yellow stuff, insulation it comes in thicknesses up to 4" I think. You'll also have to have two "sound proof" acoustical doors. Be sure to use mufflers on the vents, damping material on all duct work, and have them run flex duct where ever possible. In IN the limit is 14' on the flex stuff. Great stuff foam around all the electrical boxes and light switches. That means no P-rings, you have to use boxes on this one.

Here's a pic on floating floors.
If you like what you see then I would read Auralex's white papers, and they 5 chapters at Acoustics101.

My assumption is that the client is not completely informed of what "sound proofing" entails. Be sure to explain that it's not possible to be "proof" and that coming remotely close is terribly expensive and possibly an inconvenience/eye sore (two entry doors 6 inches apart; having to step up onto a floating floor). He may change his tune all together.

I'd also consider a rubberized spray for inside the upper ceiling which will be right under the floor above. Rockford used to make one called noise killer, I'm sure dynamat still makes one. You'll need to check local codes before using it of course.

Doing the research yourself and having plane jane framers, drywallers, insulators do things your way will be much cheaper than contracting it out to a studio. The headaches involved may be more than they are worth however...

Remember Ed said = hire a pro.

Patrick

We work with one very high-end builder who told a customer - 'no problem we can sound-proof that room.' He went and did the research, built it well - room within a room, staggered stud walls, etc... Sorbothane and quiet rock on the ceiling...

The lead carpenter was really excited the day he thought he was finished (no seating or system, but the carpet and walls and ceiling were done. He took a boom box and put it in the middle of the room and turned it up (not even that loud), went upstairs and realized that not only could he hear the music, but he could understand the words.

luckily, the homeowner was so overjoyed with the theater that he forgot all about the "sound-proof" thing, and has since had us do two more of his houses and his boat.

Once in a while these things have a happy ending...:)

What do you think they missed?

Door(s)?

Ceiling / wall penetrations?

HVAC ducting?

Construction that "short-circuited" the mechanical isolation?

I'll third the motion!!! You really can't isolate or soundproof 20 hz bass at 125 db very easily!

I wish I knew...

They didn't ask, and we didn't want to wander around scratching our heads and reminding the guy about our failure, so we just moved on...