acoustic placement/small bright room


I have been dealing with this for about 6 months at least. I have a 13 x 12' room and have been stuck with brightness, actually glare that is a pain to listen to. I have room tune that helps with the imaging but the only thing that I have found to tame the brightness somewhat is absorbtion. I put quilts on the wall, all walls to be exact and it looks like overkill. Everything that I have read on the internet seems to say that it is a bad thing. But it is absolutely necessary to make it listenable in this small room.

Question is has anyone every dealt with this anamoly? Better yet has anyone solved it?

Oh, this is not hardware related. That's usually the response I get.

Thanks,
Rob
robm321
You're correct in figuring it's your room, it usually is. You can try to get the speakers positioned so that they crossfire in front of you a couple of feet. Also some bass traps can help. These aren't cheap but will help significantly and can be inexpensive if you build them yourself. Go over to AA and search for a Jon Risch DIY bass trap. Another possibility is either digital or analog equalization. This can help more than hurt in many situations. As a matter of fact I've no doubt that most audiophiles are listening to sound that isn't near their systems potential because of room acoustics. Being as you can get away with quilts on the walls you should invest in some at least 3" or 4" wedge foam and do it right. The foam will absorb down to much lower frequencies (250-500 for the 3") You can just use spray adhesive to hold it up. Do your entire front wall behind your system. Both side walls about 4' out and the ceiling the same as the walls. Last possiblity is get speakers with pots for the tweeters.
Small rooms require much more damping than larger rooms. You actually can't have as long a reverberation time in small room as in large room without this ill effect you've experienced. This is because for the same reverberation time there are many more reflections and paths that cross the listener. The result is a very muddied and unclear sound. It's also not just in the high frequency--that's where you've heard it the worst, but it carries down in to the midrange as well. Then what can be worse is what happens to the bass--you can get severe bass build up in small rooms. If your dimensions are good--in the right ratios, then your problem will be minimized, but if they aren't, then you will have another issue to deal with.

My guess is that your drapes are not overkill, but they probably have a low absorption coefficient relative to pressed fiberglass. Thus you will need a lot more quilt surface area than fiberglass.
"they probably have a low absorption coefficient relative to pressed fiberglass."

Pardon the tangent, but could you please tell me if this extends to polyfill? If I am not mistaken it is used in quilts.
Thank you very much for giving me that sanity check!

I am probably going to get some fiberglass Owens 703 or something like that and cover with sheets for now. When I get into a larger room I’ll invest in full on room treatment. As the post by Rives states, I did seem to get an aggressive pressure other than from the high frequency, which I had a hard time understanding until now (midrange). Believe it or not I have dealt with the bass issue. I use corner placement with my speakers and have a bass trap in the corner behind the speakers. The bass is not boomy at all and is actually tight and not bloated.

I do lose the reverb cues and don’t get the air that I do in a larger room but the intimate studio sound is definitely still enjoyable for the time being. Is there any particular placement for the absorption that would work best? I use auralex foam for first reflections. For example where on the walls would it be best to place the panels?

Thanks again all the comments above have been very helpful.

Rob
Make sure your listening chair/sofa is as far from the wall behind you as possible. A lot of the reflective glare you're hearing is coming from that rear wall and the farther your ears are from it, the better. Also get the speakers in from the rear (the one behind speakers) and side walls as much as possible.

I have an 11 x 13.5 room and by doing this the glare has been reduced substantially. My ears are 22" from the rear wall and I'm still 8' from center point between speakers. If you can do this and the relatively simple treatments discussed above, your problem should be pretty much under control - unless, of course, it's equipment related which I know you claim isn't the case. However, believe it or not, there are speakers, amps, cables, etc. that work better in small rooms.
I actually put some 4" fiber glass in the middle of each wall and it worked to tame the brightness and the aggressive midrange. Now I am going to adjust my speakers again since I had them toed out to help with brightness. I should be in good shape now.

Thanks again for the help all!

Rob
Robm321, what about carpeting? Also bookcases filled with books.
I have the same problem but refuse to turn my home into an anechoic chamber. Right now I use an equalizer. Parametric is better than graphic BTW.
What is the best placement for absorbtion? The first reflection points or behind the speakers?

Rob
Just got back to this thread. As to the poly fill, it depends on the loft. If it's a really thick quilt and the covering is natural fiber (cotton preferably), then it's probably doing a reasonable job. If it's polyester covering then it's going to reflect somewhat. Also, the loft is small, there is going to be much less absorption. Fiberglass is about the most efficient absorber, and the higher the density the more efficient it is.