Or you can try moving the panels away from the wall. I have two panels, one behind each speaker, and they are about 6-8 inches away from the wall. I think the idea is to "trap" the lower frequencies in the created gap.

That reminds me, I need to run some frequency sweeps and graph them again. I forgot what difference they make.

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