Foam does very little to tame room reflections and what it does do is only over limited frequencies. Good absorbers and diffusers can be had from companies like GIK here on AC or like I did, built your own. Roxul Safe n Sound in a cheap wooden frame with some fabric stapled over works really well for a small outlay. Diffusers are a whole other thing for diy, much more of a project, but just as cheap to do yourself. You're in the right place for advice, lots of experts posting here.