I originally set up my garage theater as cheap as possible, just building a wall 6ft from the garage door to partition the room and painting the walls, not even bothering to finish the bare concrete block wall on one side or moving the water heater to the non theater side.

Now I am tearing it all down and doing it right. I got the water heater moved and have everything stripped down ready for the next step, but I can't decide which would be best.

For the concrete wall, there is not a problem with sound coming in so I don't think I need any soundproofing. These are my options...

1. Nail 1x2 wood furling strips and dry wall it without any insulation. That is the way the interior walls of the rest of the house are done now.

2. Nail 2x2 strips and install r13 then drywall.

The cost difference is negligible, but would it make a difference, or even make it worse to go with option 2?

For the back and side walls. The air handler is right on the other side of the side wall and both the back and side walls transfer a lot of sound and vibrations when it is on. I am already planning to dry wall these two walls because they have a textured finish that will not match the front wall or the new wall over the concrete block. Which would work better?

1. Remove the drywall and install sound clips then install new 5/8" drywall.

2. Add a second layer of drywall with Green Glue.

3. Screw 2x2 studs through the existing dry wall into the studs and install r13 and sound clips with new 5/8" drywall. This will leave about 2 1/2" to 3" gap between the old drywall and the new and r13 to absorb the vibrations.

Both options 1 and 2 would cost about the same, but the Green Glue will be less work. Would option 1 be worth the extra work? I don't have the budget to do both unless it will be a significant difference. Option 3 would be a less work version of option 1 but maybe the gap is too narrow, I don't have the space use 2x4's instead of 2x2's.

For the ceiling, it also transfers a lot of sound from the air handler. I can't take down the drywall to install sound clips though. The attic is filled with loose fill blow in insulation and that will just be too much work to deal with. I guess my only option here will be the same as 2 or 3 above.

Please let me know if anyone has any other ideas or which of my options would be best.

I just had another idea. The closet where the air handler is has 8" of space, maybe I can put sheets of 1 1/2" fiberglass board half way between the wall and the air handler from the floor to ceiling to keep the sound contained. Leaving a section open at the bottom for air intake, would this harm the efficiency of the AC, does it need that 8" space all around?

http://www.soundproofingcompany.com/library/articles/room_within_a_room

This might help some. Generally you treat all 4 walls and ceiling.