Sound room flooring advice needed


I'm planning a remodel of my family room, which is on a concrete slab, currently covered with 50-year-old linoleum. I'll be installing engineered hardwood flooring.

What installation method is better for sonics, glue-down or floating? My main audio system resides in this space, doing double-duty as a 2.0 home theater. I listen to vinyl 90% of the time, so I'm also a bit concerned that floating could introduce footfall issues.

Thanks for your thoughts.

Bill
wrm57
Hello Bill,

Definitely glue down. Floating would create an "isolation platform" between your speakers' cabinets and the slab which will possibily induce unwanted resonances back into the cabinets. Additionally, the floor will not allow your speakers' feet or spikes to couple into the floor/slab mechanism for positive dynamics coupling into the room. A floating or a sprung floor is also never good for a turntable.

I hope this helps.

Regards,

Dan
Floating might do as you say however glueing down to concrete could be disaster. Not sound wise but construction wise. Is your house on slab or is this a basement install?
Floating will have a higher resonance then a glue down installation. How much difference is hard to tell given their are other surfaces in the room that will affect the end result. Please consider going with carpet, for in the end that surface will produce the best sound.
I would think floating, the flooring needs room to expand/contract with temperature and humidity level.

My old listening in my old house had a Birch floor it was installed on a thin rubber mat especially designed for the purpose, your installer should be able to advise you.

Best of Luck

Peter
This may sound a bit extreme but its something that may work for you. It may be a good idea to not put wood flooring where your equipment rack will be. That will allow you to put the rack directly on the concrete, or put something else down in that spot that will be better for your TT. You can probably put some moulding around the rack so the hole is not visible. If you know where your speakers are going to be, the same thing might work for them, as well.
Floating a floor will give you unwanted resonances. Carpet over carpet pad on cement would be my choice. Spike the speakers and the equipment cabinet.
You are going to need a vapor barrier before you do anything(concrete wicks moisture). Home centers sell an excellent product that comes in 2'x2' interlocking panels that leave you with a great subfloor on which you can use any traditional flooring. Conventional hardwood over this would make an exceptional base and floor for acoustics.
If it were me, I would consider a floating maple floor in the front of the room where the speakers are. This would be on very short and tightly spaced supports to there is very little give. Then I would have wool carpet on padding for the middle and back of the room where the listening takes place. I like a more lively front of the room and a damped back of the room. Then treat the first reflection points and other wall ceiling areas as appropriate.
Look just float the hardwood to the floor. That is the right way to do it. Then put some nice through rugs down. If you have resonance problems them look for better speakers, ones that don't use big bass drivers. I am a dealer for Wilson Benesch. They are made from carbon fiber and the cabinets do not resonate and excite the room or the floor.
I worked at a movie sound stage a few years ago and they used the most beautiful leather flooring. The room sounded incredible. For example:

http://www.meridameridian.com/leather-flooring/
Tried several of the above in the past. The floating floor is a poor option for
a music room. Best so far is cork tiles glued directly to the concrete. If the concrete is too rough to glue direct, there are several concrete based underlayments that can be used to smooth the base for the cork. Leather could work too.
My room is also on concrete. A carpet and pad sound wonderful, very natural acoustics.
Regards,
Thank you all very much for your suggestions. I'm coming to the conclusion that glue-down is the way to go. My own concerns about resonance from floating have been confirmed by several of you.

My wife is not a fan of wall-to-wall carpeting, so that's out, even though I know it would be good for sound. So I'll use a huge, thick area carpet on a jute pad to soak up some reflections. I considered cork flooring and even brought in samples, but I think it'll be too soft for the long haul. Looks cool, though, and I'm sure it would be an excellent choice for sonics.

Thanks again,
Bill
I was doing the same research when I was building my music room. Ultimately, I decided on stranded click bamboo for the floor because of its hardness compared to other woods
http://www.lumberliquidators.com/ll/c/Xiamen-Click-Strand-Bamboo-Morning-Star-Click-PRQCBAMSTX5/10024105

I opted to go with a floating floor because with the vapor barrier and then the weight of the equipment on top of the floor, I never noticed any issues with resonances from the floor. My speakers are 285 pounds each, amps are 115 pounds each, turntable stand is 225 pounds, music rack is sand weighted and is also 175 pounds, with the equipment on both, the turntable and equipment stands, there is very little to be worried about resonance from the floor interaction, due to the mass. I did add carpet under the racks and speakers so as not to scrape the floors and to further isolate the equipment from the floor.
Ciao
audioquest4life
Gluing to a concrete basement floor is a mistake due to wicking moisture. Floating floors work wonderful for room acoustics. Your always better off mounting turntable to studs. You can brace and beef up during wall construction so table is completely isolated.
Gluing to a concrete basement floor is a mistake due to wicking moisture.

Zenblaster, solid hardwood floors, of course, cannot be glued down below grade. But in talking to contractors and doing research (okay, on the web), I've learned that engineered hardwood flooring is designed for this application, provided a proper moisture barrier (4-6 mil of plastic) is under-laid. Are you saying it's still a bad idea?

I'd certainly rather do a float if only because I could leave the old linoleum squares in place. My gear and Adona racks are pretty heavy; my 90 lb Sound Anchor speaker stands don't pass much resonance that I can sense; one of my turntables has a 100-pound plinth and the other is on a Minus-K isolation platform, so I doubt they'd be much affected by footfalls or vibration. I'm not certain that resonance would be a problem with a floating floor, especially using a dense foam underlayment. But my system has evolved and been tuned while being spiked to the slab, so I don't want some big sonic curveball. Obviously, I want to get the flooring right the first time.
I'm not certain that resonance would be a problem with a floating floor, especially using a dense foam underlayment. But my system has evolved and been tuned while being spiked to the slab, so I don't want some big sonic curveball.
Indeed. I can't say from experience whether you'd have resonance issues or not (though like you I'm inclined to think not). But you're accustomed to speakers which are firmly fixed to an immobile floor. Any compromise there will let the speaker cabinets move, and that softens dynamics and smears each waveform launch.

I've heard this in many setups including early versions of my own. The slightest elasticity beneath a speaker is audible. A floating floor might be preferable in the listening area, but not beneath the speakers.
I had a similar experience but in reverse. I had my system in a second floor apartment and moved to a house where I have a dedicated listening room in the basement with carpets directly on the slab. In the apartment I had to plug the speaker ports to keep the system from sounding too boomy and in the basement I had to remove the plugs to keep it from sounding too thin. From the mids on up the sonic signature was similar, but from the upper bass on down the difference was staggering. There are obvously lots of variables here (although the rooms are similar in size), but the point is if you've got your system sonically where you like it on the slab you might hear something much different on a floating floor.

I'd recommend some kind of moisture barrier and a relatively thick indoor/outdoor (i.e. mold resistant) carpet to avoid using padding in case moisture ever becomes an issue (which, in a basement is not all that unlikely for any number of reasons). If the carpet gets damp or wet you just dry it out and put it back, but padding will have to be replaced. Depends on your situation. Hope this helps and best of luck.
Bill, Zenblaster is spot, I just did this last year and it sounds great. Best of luck...
Wrm57-
I have been involved with residential construction for 30 years and have built dozens of houses on the CT shoreline in the $1m range.
Is this a below grade basement? Are there any existing water issues in this basement or any drainage issues outside the foundation? water is always the biggest concern in a below grade basement.
If you live in Vegas or Az you won't have to worry about moisture but if you do. We use the 2x2 interlocking subfloor that is rubber like on the bottom and a osb on the top. You can put a floating (engineered)floor over this and your speakers will be solid as if they were on the concrete itself. I would mount turntable to stud walls as a matter of best practices.
I have used this product in the past and it's great.
Dricore
Hi Zenblaster,

Thanks a lot for the helpful response. I'm in the SF bay area (near the bay), so it's typically dry for eight months and rainy for four. The heavily-sloped property has no apparent drainage issues. The space itself is more on-grade than below, with no seepage issues; but some of the original linoleum tiles, installed in the mid-1950s, have popped from efflorescence, so moisture has obviously come through the slab at some point.

The Dricore looks like an excellent product, if a little pricey. Do you need to install a separate vapor barrier, like 6 mil plastic, too? Does the engineered hardwood flooring go right on top of it, or is another float layer needed?

Bill
The good news is that any water issues would have shown up long ago. That said, I would treat the floor as though it was a shower base. They have a waterproofing that comes in a 5 gal buck and you roll it on, as waterproof as a swimming pool when it dries. Make sure your concrete floor is relatively flat and clean. Roll this stuff a few inches up the walls and you are ready to go with the Dricore.
There are several companies that make similar products to Dricore and I would check them also to get the best for what you need.
You can contact me by email if you have any questions that might not pertain to this thread.
Good luck with your project, do it right the first time.
are you talking about a swimming pool? I remember when I built my listening room as a separate building deep into the earth my wife claimed it would have been better if I had decided going for a swimming pool.
Nevertheless when you have the chance to build it up I would go for a good concret basement, some layers of isolation treatment, then a wooden floor of heavy large pieces at least 40 mm thick. On top of that I would work with carpets and isolation treatments again as you are already doing. Don't forget a proper treatment of the walls and the ceiling. This is such crucial. It is not only the floor. The waves have to be vaporated at the side walls and also look for proper reflections of the different frequences coming from the ceiling in front of your listening chair. This is very important for the real good sound you are going for. Good luck, too.
Great info, Zenblaster. After the Dricore is down, you're talking about floating the floor on top of it, right, not gluing? If floating, what kind of underlayment do you recommend between it and the flooring? I've considered cork, PE foam, and a product called Quiet Walk. What do you think?

Pops, I looked at your system page. Your floor is gorgeous. Looks to be birch, which is what I'm planning to use. Did you float it on top of the Dricore?
The engineered flooring will come with a padding that you can lay right over the Dricore. Lock all the flooring together leaving a little short all the way around for expansion.
Do all your walls and ceilings first, right down to the finished paint.
Install finish floor.
Install base trim and shoe mould to cover the expansion gap.
Enjoy for years.
I used a floating cork floor in the basement. It sounds great and cork is very resistant to moisture.
I've seen 30 year old cork floors in expensive bathrooms and they look great and feel great on your feet, especially in the Winter. I wonder however if a full cork tile floor would over damp a room from an acoustical standpoint.
Cork is something I've considered but I'm concerned it would be too soft. I brought in some samples; I can dent them with my thumbnail. I'm also wary of it fading in sunlight, of which my room gets a ton.

Acoustically, I doubt cork flooring would damp more than wall-to-wall carpeting atop a pad, which people seem to like in sound rooms.
I have a floating cork floor in my AV/ family room, which is on SIPS not concrete. Denting is not a problem, I use flat "coasters" under heavy equipment legs and even a 8 x 4 pool table with 2" slate..literally weighs about 900lbs. but chairs and couches are not a problem unless they have pointed contact points.... The cork is subject to "tearing" when dragging stuff across it ie equipment with pointed anchors etc. My room has window walls on three sides and fading has not been a problem... Very happy with the choice after investigating about all other possibilites.... wife really likes it especially in winter because it always feels warm and soft. You do have to be a little careful about cleaning up spills quickly unless you seal it.