Concrete or Wood floor in listening room?

Dave,

I'm not saying that I disagree with your sub floor. If you built it the way you discribed, you did it right. It must be solid. I'm just not sure if it really has an advantage or not.

There is nothing special about my block walls, except they are built like your sub floor. Cinder blocks, 2x4's on sides, and foam panels in between, but covered with drywall. I can go outside the room with the all 10 speakers plus the subwoofer cranked up and place my hand on the outside of the walls and feel almost nothing. I have another room in my house that has stud built walls where I have a two channel horn system without a subwoofer. When I go outside the house and put my hands on the walls I can feel them flexing. I can also hear the music almost as well as I can when I'm in the room. I can't turn the volume up as much as I can in the theater room, because of room distoration. The walls and doors are moving the windows rattle, it's not good.

The theater room is 17' by 30' and has grown too small for all the speakers. I'm now drawing up a new room that will be 24' by 32'. I'm not saying the size is perfit for my system, but it should be better, and is all I have room for. Now you have me wondering if I should try your sub floor.

Sorry Mike

I should have been more clear. You have nothing to lose from the benefits that cement floors offer over most wood floors which are raised and set over a foundation or basement. Most have spring to them (not a good thing) along with other problems that result in poor vibration control.

A solid well constructed sub floor can offer many benefits over carpet/concrete only.

You can string wires.
It offers warmth to the room (I live in Michigan}.
It absorbs bass, concrete may be a good isolater but it is not a good absorber...pad and carpet absorb almost no bass.

Of course these are my opinions as A/B testing would be hard to do. Maybe Rives will see this thread and pipe-in on which method he would go with as he may have had a chance to do an A/B with before and after measurments.

Dave

Thanks Dave,

Mike

Dave,
I posted at AA on Rives thread also.

Mike

I am also in the process of constructing a listening room, and am installing wood floor over slab. Out here in the Pacific Northwest, we like a moisture barrier over our slab, so this is what I am doing to install my floor.

1) Clean slab and paint with a sealant. In this case I am using a product by AFM-Safecoat, as it is non-toxic (non stinky) and the slab room is already enclosed as part of my house.

2) As an added moisture protection, I am laying 60 mil plastic sheeting, a single piece.

3) I purchased 2x6's and ripped them down to 2.25". They will be used as sleepers for the floating floor.

4) I purchased 2" thick foam for insulation, and will rip that down to 10.5" wide slabs to place between sleepers. This will give me a 12" spacing.

5) Floor goes down - 0.75" tongue'n groove, bringing the new floor up to 3" above slab.

The main reason I write all this is to advise about the moisture barrier. Plastic alone will likely do. But if you want more, be sure to use something that is friendly to your indoor environment - not something like asphalt foundation sealer (which really stinks!).