I agree with zmanastonomy that treating a small room is critical. Mesch has a good idea as well. I did the same thing but it wasn't intentional.
I started out with several 4x8 bass traps from Ready Acoustics. In the big scheme of things, these are relatively inexpensive and allow the user to modify if they have the time and tools. I started out from the recommendations of the manufacturer at first and then played around with positioning. ( I'm lucky that I don't mind putting holes in my walls and the WAF isn't a factor at the moment). This is informative as it gives one real time experience in how they interact with your room. As my system has progressed through the years, I've found that better sound has come from removing, adjusting and repositioning as well as modifying.
I started out with several 4x8 bass traps from Ready Acoustics. In the big scheme of things, these are relatively inexpensive and allow the user to modify if they have the time and tools. I started out from the recommendations of the manufacturer at first and then played around with positioning. ( I'm lucky that I don't mind putting holes in my walls and the WAF isn't a factor at the moment). This is informative as it gives one real time experience in how they interact with your room. As my system has progressed through the years, I've found that better sound has come from removing, adjusting and repositioning as well as modifying.