The biggest difference will come from proper speaker and subs placement, once you have that dialed to perfection, then use treatment. Despite claims from many acoustic panel manufacturers, treating anything below 45Hz becomes impractical because the depth needed for each panel, and if you have the space to put these 10-12 inch deep panels then you are killing your music. 2 subs or 3 or 4... and will do wanders to your sound. I use REW and a $100 calibrated microphone and in 2 days I got as flat of SLP as you could ever want, my living-music-room is also a mess, windows, vaulted ceilings, skylights, L shaped, fireplace and the hole house is made out of wood, wood floor that floats and plaster walls. Just the house is a resonator LOL. I will try to post some pictures again so I can illustrate what I am saying. I had a sound engineer to see my room, he brought these beatifull bass traps the size of couches ($3k US each) after I sent him my initial measurements. If the traps would have done anything good to the room I would have considered them, but they did not even touch my room modes, an sucked the life out of my sound. I bought first a second sub, and after a day and a half playing around with REW, listening the different positions literally the room became like a symphony hall. Nothing short of amazing. The best $100 investment I ever made, in my rooms in Spain I paid a sound engineer to do this and we spent days fine tunning, after he left I was nothing short of amazed. I learned a lot and when I was in the USA last I had a ton of free time so I tried it myself. Easy as it can be, just patience, time and notes after each ready and listening.
