Also, consider sealed designs, such as Merlin monitors. Prior to my current setup, I was using Tyler acoustic monitors that were front ported. They were very good, but I could never elimnate a degree of "bloom" in the lower frequencies in my 11 x 20 room. On a whim I plugged the ports and found that they integrated a lot better with my room. Based upon results of the experiment, I replaced the Tylers with the Merlin monitors, which are sealed, and they are excellent in my room. I've even added a pair of sealed subs with great success. YMMV.