This may not be exactly what you want to hear, but there is no simple solution. I would recommend a great book the helped me out - The Master Handbook of Acoustics. - by F. Alton Everest. There is a Third Edition due out in October of 2000, but the second Edition is very good. In my room I concentrated on direct reflections, flutter echo and then bass management. I have RPG Skylines and ASC Tube Traps and will probably also end up putting RPGs Flutter Free on one or two walls to reduce the flutter echo. Also ASC offers a service for doing a MATT test - if you are computer savvy then you can do this test at home with a good sound Card and a microphone. RPG also has a software program for speaker placement with the goal of minimizing room modes. The program also offers suggestions for the location and type of acoustical treatments. Hope this helps. Keep digging the reward is worth it.
Listening Room: Diffusion vs. Absorption
I am setting up a dedicated listening room and have been looking at different acoustic treatments. Currently, the 12"x17" room is highly reflective, and actually hurt my hears when my system is played at any decent volume, I stapled Fiberglas insulation at appropriate points in the room and my ears no longer hurt but the room sounds dead, w/ no ambience. I had been planning to use acoustic foam to dampen reflection but am now thinking about solving my problems by using diffusors. Anyone have any experience in this area? Will appropriate use of diffusors give the room more ambiance? Any experience with RPG Diffusor Systems or their BAD Panel, Omniffusor, or Skyline systems?