Best treatment for basement ceiling?

MrGlobe

Hello,

My main listening room/media room is in my basement. It is a 13'x11' room with plywood walls. Currently, the concrete floor is covered by carpet, as well as the wall behind the seating area. I have also covered half of the walls on each side of the seating area 3' high with carpet. Additionaly, there are 18" carpet squares placed in a grid pattern (6 behind each main L/R speaker) on the front wall. I am wondering what a good next step is, whether it would be bass traps in the corners, or to cover the ceiling with another 12'x12' piece of carpet.

I have been reading around and it sounds like people are suggesting a hard floor and soft ceiling, is this correct?

Should I use Owens Corning 705 or something like that as opposed to carpet?

Thanks

Globe

mshan242700

http://rivesaudio.com/resources/listening_room/frame.html

http://www.gikacoustics.com

CoolJazz

What is it your trying to do? Improve sonics in the room? Greater isolation from the room above? Do you have slap echo or low freq. nodes? Multi-channel set up or two channel? Complaints as to something about what you hear?

The more you tell, the more specific responses can be...

MrGlobe

Fair enough, well theres definitely plenty to tell.

I don't care at all about isolation, I live in my house alone. I use the room for both HT and 2ch, and have only a 2 person loveseat in the room for seating. The screen is on the long wall (13'x11') and the only real opening is the doorway which is in the back left corner of the room on the side wall (from seating position)

Currently, the speakers (m70s) are ~1.5'-2' out from the back wall, and about 6' apart. I am sitting approximately 7' from the screen, and have a slight toe in currently. I have complete control over the room/decor whatnot, and I don't care how ugly it looks, I want good sound.

I am working on speaker placement, trying to get that exactly right.

There is an armoir that houses my TV, center, and AV components between the L/R Main speakers, it is made of wood and is about 5' tall and about 3' wide. I assume a wooden box that big isn't going to help accoustics at all but I haven't found anything else yet, and don't know how truly terrible it is.

The celing is open to the floor joists of the floor above, I was thinking of carpeting the entire ceiling.

The side walls both have carpet 3' high covering the back half.

Can provide measurements/pics if needed.

Thanks

Globe

Gaara

Step 1 - Stop putting up carpet. Its only going to affect the highs and do very little for the mids and do nothing for the bass.

Step 2 - Get your read on, sites like Real Traps are great for basic info.

Step 3 - Figure out what issues you are trying to solve. Boomy bass? Slap echo? Ringing?

Step 4 - Make decision based on information attained in Step 2 and the issue determined in Step 3.

P.S. Ethan has a specific video on room treatments for small basement rooms like yours. If I recall correctly the most cost effective treatment was filling the ceiling cavity with lots of OC 705 or the blown in insulation.

MrGlobe

Damn, and I like to look of wall to wall carpet so much


In truth though, my system was setup in an empty room with painted walls and hardwood floors before the basement, so pretty much anything sounds like an upgrade.

Honestly, when I listen to music, the highs are very strong, and typically the reason I have to turn it down, as they good too loud.

I have been reading about bass traps and what not, but I don't know the first thing about placing them. On a related note, the subwoofer is currently in the corner (with concrete block walls on both side) but I have heard and read that this is not always a good idea, opinions?

Furthermore, I am increasingly deciding that I need to do something about the ceiling of my listening room, especially since the joists above run parallel to the listening/viewing area. I think that owens corning 705 sounds like a good solution, however I am worried a little about price.

TECHNOKID

http://www.polkaudio.com/forums/showthread.php?t=84121&highlight=bass+traps

http://www.youtube.com/watch?v=iyYUpkpL0gw

MrGlobe

Haha yup, finished reading those about an hour ago.

Been all over the internetz today, Anandtech to GIK to Polk forums to AVS and so on

I'm going to be doing some 7' tall OC 703/705 bass traps in the 4 corners, as well as possibly some behind center/ front center.

I have also decided to use the Monitor 40s for surrounds, I am going to be wall mounting them in the back L/R corners near the ceiling

MrGlobe

Well, I've got 6 4'x2' Roxul Rockboard 60 panels on their way to me. I'm excited about getting some real sound absorption in my HT room.

Anyways, I want to place the 6 panels wherever they will sound the best. Granted I will be placing/moving them alot when I get them, but what are your opinions on where to start?

I was thinking:
(2) 1 each in the front corners, about 2' off the floor
(2) 1 each behind the front speakers, about 6" off the floor
(2) mounted at first reflection points on the ceiling, forming a 4'x4' square.

Thanks

Globe

CoolJazz

Hi Globe,

Those 6 pieces may be a good thing to experiment with and get you started but also not be enough to do all you need. You can play around with it some and get a feel for what deadening properties do for you and see where you want to go.

The first reflection points are a good place to start. From your description of the ones behind the speakers, I couldn't get a picture of what you're doing there. But with a forward firing speaker, I'd think of side wall reflection points first unless your room and positioning is such that you're a long way from them. Then the ceiling might be good. On the forward wall behind the speakers, the first place I'd try would be a piece or two centered if you can depending on that screen. So much stage depth develops from my experience with treating the front room center.

Another place to consider is the back wall of the room behind you directly at the spot the speakers face. Especially if you set very close to that back wall. A trick there is if you do have the hf attentuated, you can back the setting position up closer where low frequencies tend to rise and therefore change the overall balance.

Your corner idea while good generally, is for low frequency buildup which you don't directly mention. To get an idea of how lows play in your room, try finding a piece of music with a longer stretch of low frequency information and get up and walk around slowly and see if you can tell weaker and stronger places. How much or how little you have problems has to do with the total size of the room dimensions.

Try standing pretty up against the back wall where it does most often tend to build up and try to detect overblown bass and after you can hear it start moving slowly forward and try to find another spot where build up again occurs. The distance between those two spots would tend to repeat again at the same length going forward.

You mention the highs getting too much for you. That can be do to just overall brightness of the room and can also be due to the electronics in play. So do keep that in mind. Every piece, including to some degree the cabling can effect the clarity of the music and how natural it sounds. I'm not really refering to boosted highs as in an eq but more how real it sounds. Distortions that wear on the hearing are an indication, from whatever causes it, that it just isn't natural to the ear and brain.

If you can't get far enough testing with the 6 pieces, remember that you can temporarily add to that by using things like comforters that are also pretty absorbing. The heavy moving blankets are used in all kinds of situations in movie sound for that reason.

The woofer being in the corner can work. Especially I believe if you have a matching second one in the opposite corner. The trick is to set them up to just where you can start to hear them...then back it off a tad. That's a real good starting point. They shouldn't jump out at you level wise that they are even there. Just produce lowest of lows when called upon. The corner gives maximum gain and can be useful to lower the level control and lessen the cone motion and therefore distortion. A lot of experimenting is good to get the bass right.

Good luck and keep us updated and ideas going. Everybody learns that way!

CoolJazz

MrGlobe

Thanks for the input jazz,

The panels arrived today. I will be taking pics and whatnot in the next couple days to hopefully get some polkies opinions on where/how the panels should go.

I think that I might only put 4 of the panels in my HT room, and then the other 2 in my 2 channel room.

My newly created 2 channel room (that used to house my amazing Monitor 100s) is a 12x10 room with high gloss painted walls, wood floors, and almost nothing for furniture. Where would be the best place for the 2 panels I'm going to put in there? Behind the speakers? In the front corners?

I am going to work on room acoustics for both rooms tonight, I'm sure i'm going to have alot more questions

Globe