Have you treated your listening space?

The room, and the way you treat it, is everything. Until you get it 'right', you will never know how great your gear can sound. Only a dedicated listening room, properly treated will lead you to truly know what 'high fidelity' sound is all about. Strongly suggest that you read Toole's 'Sound Reproduction' book at least once each year, especially when you are thinking about spending another dollar on gear and not room treatments.

A comment on Roxy54's people will pay for room advice. Not so, and Jim Smith of 'Better Sound' can attest to that fact. Jim has found that many people with $100K systems will not invest a few thousand in 'professional help'. Those are the people that would do their own heart surgery, if possible. They leave so much 'sound' on the table, thinking the higher the cost of gear, the better the sound. Sad.

luckily, room treatments were one of the first things i bought into after asking for advise here on agon. only spent a few hundred bucks but the results were priceless. i'm still tinkering around with it all but am definitely headed in the right direction.

biggest improvement for me was from heavy curtains. $30 at target which i then had folded over to double the thickness (+$15 to have them stitched up). incredible improvement for $35!

I agree with Levy03, except for his math. ;)
But I think it also depends on the room. If you have your system in a room with only two chairs, as I do, then treatments are an absolute necessity. If you are using a living room or family room filled with furniture, then not so much.

I don't have a dedicated room but the largest improvement was when I installed 16" ASC Tube Traps in the front corners. No other traps dealt with the bass as well. A tightened bass resulted in big mid range improvements by removing the bass smear that affected definition there.