Sound deadening a 'hard' room

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videobruce

videobruce

Tower Operator
I have a problem with reverberation in the room I built for my layout.
I added a 'indoor/outdoor' carpet to the lower half of all the walls below the table, but that did little. I added a 'runner' carpet down the middle of the floor not just for noise but to isolate my feet from the cold concrete floor, but that didn't do anything more.

I'm think of finding a light blue carpet for the walls above the table since those walls are now painted light blue to simulate the sky, but I don't know if that will be enough.

The ceiling is not a typical 'suspended ceiling' as I didn't have the additional clearance due to furnace ducts and didn't want to give up any more height. I assume the best location would be the walls vs the ceiling anyway to be the most effective.

Other than carpet I also thought about cork rolls, but never had any experience with anything like that. I also know there are 'acoustical' material specifically designed for this purpose, but aesthetics are a issue. I don't want it to look like a recording studio.

Ideas?? (pics don't show the carpet on the floor);
 
When I added the rug (that isn't shown) it made no noticeable difference. It's a unfinished basement in a 95 year old house. There is a humidity problem and some seepage from some areas on the walls (though not in this area). I wouldn't/couldn't cover the entire floor, especially with padded carpeting.

The problem is the table, wall & ceiling that forms a 'U' (2nd attachment shows it best) making it a great echo chamber.
 


Add a lot of scenery! No hard shell though. Acoustical tiles on the walls might help. A scenic divider could change the shape of the room to help stop the echo effect
 
Did you insulate the walls at all?
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No, no need to. this isn't a transmission issue from outside the room, but only an absorption issue from within the room.
How would insulation outside the walls help??
 
You have way too many hard, flat surfaces to reflect sound. Once you start to break up those flat surfaces you will notice the difference. Really all you need to do is fill your room with crap!:D Storage bins or cabinets under the layout will break up that area. Your landscaping or buildings on the layout will also help to diffuse the reflections in the upper portion of the room. Any empty room like yours, carpeted or no, will reflect sound until it's filled with something.
 
You have way too many hard, flat surfaces to reflect sound.
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I'm painfully aware of this now. Something I never thought of at the time until it was too late though I don't know what I could of done to do anything about it without it being something drastic. Drastic and me don't get along.
I have contacted a supplier (previous link) and mentioned some of the suggestions already mentioned. The tiles can be purchased individually by phone at a lower price than posted on their site which is good news. Doing anything with the floor is not the answer. Carpet is not "broadband" enough to do much good is the answer I received. I'm waiting for his reply after a e-mail was sent with specs and photos.
 
I wouldn't do anything other than start filling that way to clean of train room with 'stuff'. That will do more than any acoustic panels or treatments. Good luck with whatever you do.
 


I would make triangle pieces in 1/4" plywood that fit into all your corners where they meet the ceiling. Behind it put a plastic bag of old rags or sponge. do it for each corner. Make them about 14" -18" on each side. Under your layout, try to pull boxes n such out about 5-8" from the walls. This is about as good as you're gonna get in that room, until its filled with stuff.
 
Probably more effective than carpet, and possibly cheaper, would be egg crate material.

EC2-5-S.jpg


It can be easily attached to the wall under the table, the underside of the table, and the ceiling.

You might even be able to find it in a pale blue for the ceiling. Though I imagine the grays would be good for under the layout.

http://www.onlinefabricstore.net/fo...els/3-54-54-acoustic-egg-crate-foam-blue-.htm

If you really wanted to go nuts with it you could get the big triangular stuff, but I can't imagine it really being that much better than egg crate, and it'd look pretty weird and take up a lot of space.

http://www.onlinefabricstore.net/specialty-stores/acoustic-store/acoustic-panels-tiles-and-foam.htm
 
I found this article something that may work and would fit between the furnace ducts;
http://acousticsfreq.com/blog/?p=62

If I can find the material.

Regarding the egg crate foam, I already have what would be six 2' square pieces (from three seat cushions I replaced) I already tried. It did some, but didn't seem enough.
 
It seems like you're not going far enough with each of your attempts. A carpet runner, and a few foam tiles aren't going to do much for a room that size with that much hard surface. You need to cover as much of it as you can afford to, or you won't be satisfied with any results.
 
I understand.

Regarding my link to those home made panels, the material from Roxul is $47 per eight 'batts' (2' x 4') in a bundle. They are made in Milton Ontario and a local builders supply company sells them. This seems to be the best cost and otherwise effective solution if I can find matching material.
 
I went to a acoustical supplier with the following questions based on replies here and elsewhere. Below is what was said, his replies in bold;
On Tue, 06 Mar 2012 12:35:53 -0500, Mike Mohs <mike@asiproaudio.com> wrote:

A. How much a difference would drywall of made as far as the echo problem?
It would only make about a 10% improvement as you still would have all reflective surfaces.

B. Per our conversation regarding covering the whole floor with a padded rug, with those pics, how much a difference would that of made?
Almost no difference at all as the rug is not broadband enough to improve the room very much.

C. It was also suggested that I hang a sheet around the perimeter of the tabletop to see if that would make any difference. Also, it was suggested that I store things under the layout to absorb sound. neither makes sense to me, especially the 2nd idea.
The sheet will not help at all. The more items you put into the room the better it will absorb and scatter the sound thus reducing the echo.

D. It was also suggested to insulate the ceiling and walls. I don't understand why/how that would be effective since I don't have a ingress (transmission) problem, only a reverb (reflection) problem.
You are correct as this will not help the echo issues.

E. It was strongly suggested plywood was more of a problem over drywall especially with parallel walls, more so than you stated. A 'sounding board' term was used as the plywood vibrates, amplifying the sound waves.
This would only be true if the plywood was not mounted securely and it resonated or rattled against the drywall creating additional sound problems.

F. The other point that was made a big deal over was no insulation behind the plywood. The wall is open on the other side. I might see if it was closed, the hollow space between making some difference, but open?
The insulation would only reduce the echo if it was open and exposed to the room. It would have to be opened to the inside of the room not the outside.

G. As to the material suggested, the heaver weight material; is that more for bass frequencies? I do know thicker material absorbs lower frequencies better, but that isn't the major problem here.
The different weights can mean different things depending what exact material it is. We have over 2000 products so the rules can be slightly different for each one.

What would the price be for less than a full 14 pieces, per piece? I'm looking at three for the corners, two for the long wall and one for the corner by the door, a total of six 1" 3lb pieces?
If you order them with me over the phone they would be $16.00 per panel and you can order them in any qty you like.
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The cost per panel ($16 + shipping) isn't far off what it would cost to purchase a bundle (eight) 2'x4' Roxul RTH80 mineral wool fiber insulation panels ($47, $6 each) plus the cloth to wrap the material if I make it myself.
 
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Back in the day, when a friend had a king-hell stereo system (dollar-wise, not loudness-wise), he used to put blocks or pyramids of foam rubber in various places around the room. Stuff looked like the eggcrate material above.

Not being an audiophile, I have no idea if it really helped or if it just made him feel better about the acoustics.
 
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The egg crate material was used in many recording studios to get rid of the live-ness in a room. You would need to cover 3 walls and the ceiling to do it right. I would put dense items near inside corners to get rid of standing waves which made the deep bass muddy. Sound deadening and getting proper acoustics are really 2 different things.
 


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