New HT in garage project - newbie needs ideas (1 Viewer)

[Al L]

Hi all -

So I'm going through the design phase of turning 1/2 of my 2-door garage space into a HT. I've been scouring both these forums and over at AVS..trying to get as much info as I can before moving forward.

First question is: Is the space 18'long x 11.5' x 8.5' high big enough? I think it is, even though I have a 106" screen already and sit about 13' away from it.

Second question is: How do I sound proof the ceiling considering my kid's bedrooms are just above the garage space? I've thought about not joining the 2x6's directly to the existing garage roof, rather suspend by about an inch. The HT roof I've considered drywall->insulation->1/2" drywall->5/8 drywall. Any thoughts on if this will be enough to drown out the vibrations/bass in the bedrooms above?

Any help appreciated!

Thanks!

 

[SteveMetcalf]

Al: Are the dimensions you posted the dimensions of your intended ht area, or are they for the air volume in this area? If you can tell me the dimensions of the acoustic space you are working with I can give you some feedback on acoustics.

 

[Al L]

Hi Steve - this is the entire area in which to build. I guess (without accurate measurements) take another 6" off each side after walls go up for interior HT space. I could probaby stretch about another 6" wide since I may have problems placing the front speakers with the current width.

This is what I am thinking so far:

2x4 & 2x6 wood frame - 4 walls
For the walls that are external i.e. the one wall that covers the garage door and the other that seperates the garage space, I will use 1/2" greenboard overlaid with 5/8" OSB.
Insulation in all walls.
Interior 1/2" drywall overlaid with 5/8" drywall.

I am currently researching how to utilize green glue between the two layers of drywall.

For the ceiling, I am considering nailing up 1/2" drywall first before building the frame.

Comments appreciated.

 

[SteveMetcalf]

Floating the inside walls is a good idea. I think it would be appropriate to consider acoustics step by step, in addition to soundproofing, since you are currently in the design stage. If you consider these things now, any costs incurred would be signifigantly lower than if you were to modify the room afterwards. I notice that by the dimensions listed you are very close to a good room ratio. There will be some corrective action to be taken in the range of 300-400hz, but it will be easy to deal with so don't worry. Once you have floated the ceiling and walls, mid and high frequency transmission into neighboring rooms will be all but eliminated. If you want to stop the bass, you will have to absorb it. The way to do this is with bass traps. The idea with a bass trap is to create a volume-specific enclosure that will resonate at a certain frequency. Inside this enclosure would be something that will vibrate using the energy of the sound. The sound energy is thereby converted into heat, and does not escape the room. In addition this will clean up the bass response of your room, and make the listening experience better, and improve the percieved efficiency of your system. After you have isolated sound transmission and conquered the room modes, a little mid frequency absorbtion, and some high frequency diffusion would uiltimately give you one hell of a good sounding theater. It shouldn't cost a lot to do either.
There are many ways to accomplish this stuff. What is your budget? I could suggest some products or give you diy instructions.

 

[Al L]

Steve - I have not really set a budget, I was planning on doing it as I go throughout the (hot) summer weekends. I have so far budgeted for the materials to build the frame, walls and installing A/C. I am trying to get costs on Green Glue but don't know where to go for that just yet.

If you can give me your suggestions on products and DIY instructions then that would help me determine if I have the money to do it or not.

Much appreciated.

 

[todbnla]

Check this out, your not the first with this idea:

See Ron's kewl theater here...
http://home.earthlink.net/~peregrinefalcon/driftwood



He is a member on this forum and he goes by Ron-P
I am sure he can answer a lot of your questions.
Good Luck

BTW-My theater started out intended as a 2 car 20x24 garage...

 

[Al L]

Ron just updated his site with some new pics.