Audio Room layout and design considerations

nooshinjohn

Well guys, it finally looks like I will have a 20x22 foot room that will be dedicated to HT and two channel. My main focus is to build a two channel rig that can serve as a temporary theater setup from time to time. Right now, I am less concerend about gear than I am about getting the room right. It will be carpeted wall to wall, but I will need to first build the walls and ceiling. All electrical in the room will be on a 20amp circuit and in-wall speakers will be used for all surround locations except for mains and center channel.

The questions I am looking at are should I use a certain type of drywall/insulation?

In a room of this size, is there any benefit to building the walls so that they are "staggered", alternating between 2x4's and 2x6 every 16"?

How about the ceiling, which is at 9 feet? Should I have one side at 9 feet and drop to 8 feet on the other?

I guess what I want to do is eliminate standing wave considerations and build the room in the best way possible for two channel, then set up the HT, letting the Pioneer correct anything that may be off on the HT side.

newrival

Not sure what you mean about staggering, but it would be ideal if you can make sure no walls are parallell, but also symmetric. Slanting the ceiling would be good, as would making the back wall smaller than the front so that it is wedge shaped. It doesn't have to be dramatically so, just a foot or two would be great.

newrival

Also, you want the walls as rigid as possible.

Conradicles

nooshinjohn wrote: »

Well guys, it finally looks like I will have a 20x22 foot room that will be dedicated to HT and two channel. My main focus is to build a two channel rig that can serve as a temporary theater setup from time to time.

Did you get a new house? That is a very nice sized room.

nooshinjohn

Conradicles wrote: »

Did you get a new house? That is a very nice sized room.

We are going into escrow this weekend on an 1800 square foot home... basically the biggest house we can get for the money in Calabasas CA. The catch is that it has not been renovated since it was built in 1963, but it does have new windows, central air, and copper plumbling. It has a very nice layout overall, but some upgrades are definately in order.

Not sure what you mean about staggering, but it would be ideal if you can make sure no walls are parallell, but also symmetric. Slanting the ceiling would be good, as would making the back wall smaller than the front so that it is wedge shaped. It doesn't have to be dramatically so, just a foot or two would be great.

What I mean is having each of the side walls be built so they are not flat. every 16 inches, the stud behind the drywall would be two inches thicker, giving the wall a "sawtooth"effect.

I have also thought about using an expanding foam insulation in these walls and a 2 inch diameter PVC pipe that would allow me to add and replace cables as needed from the walls without having to open them up again.

tryrrthg

If you really want to do it right you might want to look into hiring some help. I've seen Rives Audio on audiogon for years and I think they helped with the design of Lavigne's room that so many audiophiles have coveted on audiogon. For the price of a decent piece of equipment they can help you get it right. I've always kept them in the back of my mind to use some day but my interest/time in audio is non existent at the moment.

http://www.rivesaudio.com/services/servicedetails.html

http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1036349020

EndersShadow

John, your talking about a staggered wall where the stud's on each side dont connect all the way through. This is recommended as it keeps the sound from passing through the studs to the drywall on the outer side of the wall.

So what you do is actually use a 2x6 top and bottom and put 2x4's alternating which side they attach to on the top and bottom plates.

Call me later tonight on this.

unc2701

EndersShadow wrote: »

John, your talking about a staggered wall where the stud's on each side dont connect all the way through. This is recommended as it keeps the sound from passing through the studs to the drywall on the outer side of the wall.

So what you do is actually use a 2x6 top and bottom and put 2x4's alternating which side they attach to on the top and bottom plates.

That's the right process for preventing sound from bleeding into other rooms (or bleeding INTO your listening room), but that doesn't do a whole lot for in-room quality. Judging by his "sawtooth" remark, he was thinking of having the DRYWALL zigzag. Which frankly would be awesome, but a huge pain in the butt- all those corners with drywall would be a bear to mud and the other problem is it's not something the next owner can rip out. Oh- and what about windows/doors?

What's above the ceiling? That slant you mention would be great, but difficult... If it's attic space, that's where you put your bass trap that'll suck up a lot of the bass standing waves:Replace the ceiling drywall with fire-treated accoustic fabric, do slats above that (alternate direction between joists), OC703 on top of that, then build a basin in the attic that'll hold about 4 feet of blown- in. The slats diffuse the high freqs; the bass gets absorbed by the insulation over it. If it's too dead, you just dig back up the insulation and replace some of the OC703 with drywall to liven it back up.

Make the back and front walls curved out or just cheat it out a little in the center so it comes to a point. You don't need a ton- just enough so that you don't have a flat surface back there.

Everywhere else, you leave normal walls, unless you want to do the isolation thing with the 2x6 top & bottom that Bean is talking about. Build your treatments on top of the drywall there.

shadowlight

Could you potentially leverage something like Cardas Room Dimensions