Room treatment is highly overly expensive? What a load of BS. What type of equipment do you have in that big mother of a room? I'll bet it's expensive enough that decent room treatment from any of the recommended vendors amounting to less than 20% of the cost of your gear will yield better results than all of your electronics combined would yield. If you have low grade mass produced consumer equipment, then I retract my statement. Its been stated many times that room treatment (or acoustics) is probably the most important part of a system, but it's often overlooked because people "think" it's expensive or has low WAF. But in fact its neither that expensive when taken in the right context and perspective and it can integrate in to the decor as well. DIY if you want, but frankly for under a grand you can get some effective bass trap coverage for starters that will blow your mind. If your a pro audio guy, check out the acoustic boards on gearslutz where there is lots of discussion on DIY room treatment.