Coupling vs. Decoupling for Bass Response

My work system is in the hay loft of a converted 100 year old horse barn. The floor is wide pine planks over wood beams and shakes with just the footsteps of someone walking across it. Needless to say it does not help my bass response. I have my LaScalas in this room, which are not exactly known for low bass in the first place. They have a rather large footprint (I believe around 2X3 feet). Any suggestions of some simple (re: inexpensive) ways to get back some of my bass that the floor is eating up? I'm currently using three cones under each speaker, but I'm thinking coupling may be counter-productive. I'm guessing that I should be looking at a means of decoupling. Thanks in advance for any suggestions.

Yes I bet the cones direct energy into that large floor and make it sing along some.
I once constructed Platforms boxes out of Medium density fibreboard.Like a big sandbox with close fitting floating lid.It helped some,would have liked more performance for the effort.The system was in large second story room.Floor was about 14x20 no center supports underneath.I placed the speakers close to outside wall where large floor is better supported.Have you dealt with middle area where floor is prone to most movement.Picturing the barn loft must have some ground floor up supports already,can strategic ones be added?Maybe more support from ground floor under speaker locations and other loose areas.A second skin of flooring in the area of speakers or even complete platform in that part of the loft.Also club stores like Sam's ,Costco have these 6x9' area rugs made of Berber scraps,edges sewn real nice.They are about $30 each,real inexpensive stain resistant.Several can damp a resonant floor as good as the sandbox did.
We think alike......some random thoughts - I would experiment with some simple dense padding such as used in workshops to keep your feet off the cement floors, its very cheap, comes in large sheets and is only about 1/2 inch thick. If it helps at all you can probably improve on the isolation by adding other dense vibration absorbent stuff in layers. Another Rube Goldberg method might be to put down the absorbent materiel, top it with a sheet of soft wood and then put cones between the speakers and the wood. This would allow speaker's vibrations to disperse some and help isolate the speakers vibrations from the floor.
I'd suggest fixing the floor, which is where the problem lies, as you said yourself.

Are a few well-placed 2x4 or 4x4 support beams too expensive?
Thanks for the suggestions so far. Tom - I only lease the space so structural renovaitons are out of the question, otherwise I'd address that. I may still ask the owners, but the other problem there is the expense. Floor area is over 1400 SF and it is one big room. There's a few quick snapshots I took of the system here where you start to get some idea of the space. There is at least 15 feet on either side of the two speakers before you get the side walls. I was thinking of solutions along the lines of what Newbee was suggesting. Perhaps as simple as a small section of carpet with pad underneath since I have some surplus from a project at home. Any thoughts on that?

I have found the loss of definition caused by the bottom of speakers placed entirely flat on either a hard of soft surface to be objectionable. To limit contact area, and stay low in budget I would think Vibrapods may be worth while. There are people who have tried or done this and reported on it, but I am not one of them.
auto salvage sissor jacks and beams for temporary support,plus the carpet over padding?
Jax, if you can work on the support under the floor, especially where the speakers are, do it. You might have to run a couple 4x12 beams underneath with adjustable posts, height depending, underneath them. If the support underneath, joist, posts are solid, check to see if any of the pine planks are loose or warped. Nail or screw them down. If they are shot, replace them or use some 3/4" plywood as a area sub floor. If the joist are more than 16"oc, see if you can put some additional ones in. It will cost you quite a bit to do the whole room, just concentrate where the equipment is first, then the listening area.
Hi Marco,

You are correct that the pointed spikes are coupling your speakers to the floor and their vibration is causing negative effects such as directing unwanted vibration towards the equipment rack, your listening location, possibly to neighbors, etc. Much of the speaker's energy is being used to set your flexible floor in motion rather than is producing music. Not only is your bass response being compromised but much of the musical range is being affected as well. This is the case for all suspended wood floors and is a significant issue for many audiophiles. It is also an issue for concrete floors but not quite to the same degree.

The best method to deal with your issue would probably be more expensive than you have in mind but there are a few inexpensive solutions that will be helpful. If you mass load the floor under the speakers much of the floor's flexing will be minimized. Some other areas of the floor may also benefit from mass loading. You mentioned that you are on a loft so floor jacks under the joists is probably not an option. You should also decouple the speakers from the floor and from any massive supports (the exception would be a high mass support that is also highly absorptive). There are high quality and inexpensive compliant feet available that will accomplish this. You can contact any of the major audio suppliers for a specific recommendation.

Best Regards,

Barry Kohan

Disclaimer: I am a manufacturer of vibration control products.
A 1400 sq ft room (20 x 70?)will be tough to fill with bass regardless of the flooring. A well-matched sub-woofer might be in order.

Apart from the excellent suggestions above, you might want to stabilize the speakers themselves by placing some very heavy concrete pads on the floor and then use padding material (per Newbee) and/or spikes on top of that. At least you might be able to keep the cabinet itself from moving with the bass waves. Just a thought.
It's not the speakers, it's Diesel the dog that's pounding the floor with his big paws.

Put tennis balls on each of his four feet and see if that helps.

By the way, I'm jealous that your studio is so much bigger than mine.
Sorry for not responding earlier, but I seriously suggest paying a visit to the audio asylum boards. There you will find a recipe for DIY platforms in numerous shapes, forms and sizes, but the predominant ingredient is PEF, aka closed cell polyethylene foam. It is quite a hard foam, the only way I can describe it is somewhere between a mattress and rubber :) however it does wonders. The rest of the platform depends on budget, availability, aesthetics etc. Probably the best design is a sandwhich which consists of the following:
- 1/8" aluminium (mainly for looks)
- 1" MDF
- 2-4" PE Foam
- 1" MDF
- 1/8" aluminium

You can play around with the rest of the sandwhich but the main thing to keep there is the foam. Then on top of the sandwhich place your speakers on their spikes.

P.S. Barry and I are on the same wave length. When I suggested the heavy concrete pads, I didn't specify that they were to only go under the speakers, but I hope it was clear through implication. I would not suggest 1400 sq ft of heavy concrete as that would surely collapse your flooring altogether ;-)
Hey X- You forgot the mayo and mustard! Where do you buy PE foam? That sounds like the same stuff Newbee was recommending that they use on hard floors - otherwise known as anti-fatigue that what you mean?

Albert, I seem to recall seeing some pictures of your studio renovations to accomodate your sound system....believe me, you have nothing to be jealous about!! I tried the tennis ball suggestion but he kept chasing his feet around and making even more noise!

Thanks all - Great suggestions!! I'll let you know what I come up with. As I said, the structural renovations would be most difficult and expensive so I think I'll start with the speakers and see where that leads me.

Hi There,

I am not sure where you would get it in the US/EU, but from what I read on Audio Asylum you should be able to easily order it on the net. Here things are slightly harder to come by, so I had to go to an industrial manufacturer of numerous types of rubbers and foams and get the PE Foam from them. Wasn't that difficult really - yellow pages, 2 minute phone call and that's it. I even got it for free :) cause they normally come in a huge board of around 5mx10m but I only needed two small pieces so they gave me offcuts they were gonna throw away anyway.
X- seems like you are using the stiffer variety of PE foam. I would have guessed the more squishy one is the one to go for as it would seem to offer more decoupling effect. Here's an online U.S. retailer with a description of the different types of PE foam available.

While you're decoupling them from the floor, why not couple them to the ceiling?? I do mean suspend them -- if you have beams that can take the weight.

Stop laughing, I'm serious. Cheers.
Marco, is this the system you have posted with Diesel in the picture? Nice barn! Just kidding.

I would try the simple approach first. Get big pieces of MDF and place them under the speakers. My idea is to spread out the weight of the speakers the floor joists are trying to support. The reason I suggest this is so that you can see if this cheap idea yields any positive results before investing a lot of time and money attacking it in a similar manner.

If the floors are old and creaky, platforms constructed of heavy materials may compromise the safety of the entire loft. Buy one sheet of 4" x 8" 1" thick MDF and cut it in half so you'll have a 4x8 under each speaker. If that doesn't work you might have to try two 4x8s under each.

Try the cheap simple way first! Or get Diesel to curl up in front the creakier of the two speakers.
Gumby - Yep...the WAF finally got to be too much at home and I moved that system to my studio where there's more space. It improved the soundstage with much more room for the Scala's to breath around them. But the bass suffers, per the thread. My thinking exactly on the MDF. Actually, my wife got me a yoga matt for my birthday a short while ago. I guess she was hoping I'd use it for yoga!? It's just collecting dust somewhere. It's made from where did I put that box cutter?


PS The home system is now Wright Sound AG1000 pre. Mono 10 amps, and Soliloquy 5.3 speakers. Very nice. Not as fast as the other system, but has it's own merits. Matches the smaller room better. WAF is high with the 5.3's, but the Mono 10's on their sandboxes remain a thorn... though, much to her credit, she does not complain nearly as much as she likes the sound, and surely prefers the size of these speakers.