Hello KN_Fan. The boominess can be controlled using the bass traps (the acoustic foam in the corners in my setup) the foam behind the keyboards does a great job of controlling the reflections from mids and highs. The bass traps are made by Auralex, www.auralex.com. Keep in mind the acoustic foam will not isolate the sound. It will only get rid of early reflections of the sound. I noticed a huge difference in sound monitoring right after I installed this.

You may want to check out the Max-Wall system by Auralex, I just ordered a Max-wall 420 for the back wall and a Max-Wall 211 for vocals. I will post new pictures once I get those in.