I have been trying to tame brightness for about a year now from my overpriced RTI 12's. Brightness is high frequencies. makes a SSSSSSSSSSSSSST noise. Some call it detail. I like treble myself, and can't hear too well in one ear, so i tend to like more treble than most. So when i say Polks are bright, they are REALLY bright. I just got a Denon 2910 DVD player. Nowhere near as bright as the Yamaha. Why risk it? Get the Denon stuff, pay just a little more, it's worth it. Denon is considered the best for a reason.
if you think EQ will fix it, you are wrong. The tweeters in Polks are bright. The 8's moreso than my 12's.
Trust me, room acoustics are a big part of it, but you don't want to waste time on this. The time and headaches are worth a heck of alot more than a hundred bucks or so. I should have done this all along. I bought Polks before i was educated and I am stuck with them. Not to sound arrogant as being "stuck" with $3000 worth of speakers isn't that bad, but that money would have been better spent on another brand, like Psb or Axiom.