Do most of you dampen the walls of the equipment rooom? Without a door over the equipment rack opening does sound travel in the equipment closet and create an echo or act like a large drum?

Without a door (or something) between you and the equipment rack, all the obnoxious noise created by the equipment will enter your listening space. That's not at all good.

In addition to what Dennis said, that opening for the equipment rack will allow sound to flood into the equipment room. You would need to use the same sound isolation treatments on those surfaces as well.

We see this a LOT in conjunction with stairwells. That area under the stairs makes a great cubby hole for equipment. That's what I did.

The distinct liability is that you could potentially be introducing a great deal of vibration into the stairwell. And what is the stairwell attached to?... Uniquely, the stairwell is attached to just about everything else in the house. The joists, the walls up maybe 2 flights of stairs. A very, very conductive framing element to be avoided at all costs.

I've been thinking about this for a few weeks now.

Step 1. Build a room that is "soundproof" - simple :)
Step 2. Cut a hole in it for cables to go to where you've got your kit?
Step 3. Your room isn't soundproof anymore so you throw yourself into oncoming traffic after all that work

What is the best way of bringing cable in when you've got your gear in another space? How do you stop flanking etc?

Elill ... other than your cables, you also have to bring electric and HVAC into the room and that means penetrating your barrier. There are ways to resolve that problem. Among these are:

Step 1. Drywall your room
Step 2. Bring cable plant, HVAC, and electric cables into the room by cutting through your barrier near the ceiling on a wall surface or through the ceiling near a wall.
Step 3. Seal air gaps around these openings
Step 4. Install a soffit placing your entry points behind the soffit. Line the soffit with Insul-Shield, duct liner or other fiberglass product.

Thanks Dennis, detailed instructions is most useful - especially for the soffits.

This is going to be fiddly for me come time (due to location of stuff - keep an eye out in 9 months time)...I suppose I want to get it right first time...more planning is/will be required!

Here is a basic look to what I have (not really to scale) Both doors with be sound doors. It is a room with in a concrete wall basement. The are of concern is the RED arrow going into the opening for equipment.

The blue is the concrete block and the black is the framing that will have DD+GG 5/8"


http://home.mchsi.com/~fun_pictures/Equip_room.JPG

If I put 1" on all walls and ceiling in Eq. Room will that be enough?

What is the point of a sound isolated door into the equipment room if you're going to have the rack through the wall? Your better choice would be to have the rack completely inside that room. Otherwise, you'll need to sound isolate the space to the same extent as the theater room. That will leave you with the problem of equipment room noise entering the theater area.

Ditto! Since you have an equipment room planned, keep it totally in there. Get a device to make your controls all work on RF so it can pass through the walls.

Make sure you avoid the stairwell framing like the plague.

The door at the bottom of the stairs will likely be the weak link in the end

Dennis,

I should have stated that the door into the eq room wasn't technicallly a "sound" door but it is a heavy door, weatherstripped to prevent any rattling.

When you stated "sound isolate the eq room"...I may not quite understand that part. (if using 1" on all walls is sound isolating, then I do understand)

Thank you guys

Ted,

I my interior wall is about 3 full inches away from the stairway wall. Before i built the theater wall I put 2 layers of 5/8 drywall between the studs of the stairway wall to add mass. Hope it helps, I know by knocking on it before and after it made a difference.

Very good idea. The door looms as a problem.

If the equipment room is open to the theater, as in your current plans, then the equipment room requires clips, green glue, etc. The 1" of stuff on the walls is not a sound isolation strategy.

How about making access to the rack/eqpt via the wall facing the bottom of the stairs vs. through the HT wall? Looks like you've already planned otherwise though and may not be easily changed. I was gung ho to have access through my theater wall but took it outside after weighing downside with my design.

I understand now.

Yes, the whole perimeter of the theater and the equipment room is isolated from the main house with clips, DD (5/8"), GG, and hat channel in theater and in eq room.

the only thing is the main door that will be a concern from sound going outside the theater. I am unable to have 2 doors with the amount of space at the landing. I plan on a solid door with the addition of some MDF/GG on the inside, then treat the bottom half inside the theater.

There you go. Seal up the door. See some info here: http://www.soundproofingcompany.com/library/articles/flanking

One big deal will be the seal where the door mets the floor. You'll need a threshold of some sort. Can be a strip of hardwood, or a metal threshold.

How about making access to the rack/eqpt via the wall facing the bottom of the stairs vs. through the HT wall? Looks like you've already planned otherwise though and may not be easily changed. I was gung ho to have access through my theater wall but took it outside after weighing downside with my design.

Originally that was the idea, but inspector said I couldn't remove that. There is a metal support beam on the end closest to the theater side from floor to ceiling. I couldn't justify the cost to explore.

If you have the space, a fully enclosed equipment room is the way to go. The mistake I made was to overlook the use of cheap single pane sliding doors. I guess the contractor though "inside only, who needs double pane". Well some noise does get through, not much but some.

Lesson learned, use high grade double pane sliding doors!