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. . .but my research has found that you really need more coverage spanning the corners. Those don't look very wide or thick?



The corner triangles run about 14" per side. The seams are 45"x7". They aren't thick at all. They are made with one sheet of a posterboard-like panel with some stuffing on the back all covered in cloth. The edges are stitched close. You could probably make these pretty easy.

Yes, a larger size would be better, but I have a very small room and even these "smaller" treatments have a detrimental effect on the perceived spaciousness. In this case, it's a choice of form over function.

In my experience of having small listening rooms, bass builds up in the corners and gets boomy. The corner traps, though small, really help alleviate the low frequency dominance.

I know it ain't much, but it's working for me.

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"Nothin' up my sleeve. . ." --Bullwinkle J. Moose