I have LS 50 Metas plus two SVS SB 2000 subs in a small room. I can tell you without some sort of EQ or DSP, the standing waves will absolutely kill your sound. The bass nodes can be as high as 20db above flat at some frequencies. The greatest innovation in the last 20 years IMHO is DSP bass correction. You could look into a miniDSP Umik which sells for a little more than $100, and then learn how to use REW (which is freeware) to measure your speakers in the room, and design a few simple peak filters to attenuate the peaks (the dips may be unfixable). If you do that you'll be surprised how much better your system sound. After that, you'll be better able to evaluate whether or not you desire an upgrade on the Polks.
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