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Bass Trap help



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My room sorta looks like this with the total length 25'

Im getting a rather large peak at both 63 and 80hz using warble tones and a Radio Shack sound level meter. The right from the listener opens into a kitchen. Anyway. I bought 27-Owens Corning 703 2"x24"x48" panels. Surely this is enough material? Stacking the panels 3 deep for 6" deep panels, that gives me 9 panels at 24"x48". Ive been moving them around, first trying 2 in the front corners, 1 to each side of the speakers, 3 to the rear (dead behind and one to each side, and the lasy one the wall to the left of the listening position. Zero different as read before and after using my meter.

I dont understand.

Help
jim1961jr
kevinzoe
167 posts
 
Orpheus10 wrote "The cores are very easy to decorate in order to make them invisible"

. . . or you can dress them up and make them look like architectural columns. I bought a 12foot long 48" diameter Sonotube to fill with OC701 fiberglass for a bass trap and covered the curved exterior with a red oak veneer and polyurethaned it. It's a hemi-cylindrical diffuser+bass trap in one. I'm using 5 of them: 160degree arc, two 130 acrs and a 100degree arc in the room's 4 corners and middle of the front wall. (Pics are in my System for what it's worth.)
orpheus10
8,668 posts
 
Sounds beautiful, and functional at the same time.
jim1961jr OP
9 posts
 
Just to update things......Ive moved both the speakers and listening position back about 3ft. This made both the peak less. My room (if you look at my crude drawing) is untypical in that its not a rectangle. So moving the listening postion back into the more open area that flags right into my kitchen helped with my problem. Im now closer to the back wall which isnt great, but the extra space behind the speakers has made more a deeper soundstage (which is good!). The sacrifice was minimum in that the detail in middle suffered mildly, but barely noticeable.

Ive come to the firm conclusion that the bass below 100hz or so just cant be tamed unless you are willing to spend a great deal and a few feet of absorption material in every direction and corner.

While all the OC 703 I bought did little for the deeper bass, it did help a bit to clean up the upper bass and lower midrange.
hotmailjbc
571 posts
 
i agree. this bass boom in my room was awful. but with the tubes, 4 cathedral panels and the room tune upper corner pillows[4] i have made a lot of progress. and it is somewhat uniform. before i made the additions the bass changed in many different regions of the room, for the worse. unlisteneable
stops
56 posts
 
This is a different slant. I had standing waves that correlated very well with the room dimensions. I installed a lot of absorbers which helped somewhat but Physics is phsics and I still had standing waves, I opted for a subwoofer and a crossover for it (Velodyne SMS-1 but there are cheaper units see The absoute Sound article by Greene). This enabled me to move the subwoofer for best bass response without messing with the main speakers. It is more expensive than panels but will give you very good results.
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