Okay so as this very informative topic comes to a close, let me ask one final question before we put this to sleep.

When putting any kind of treatment on a wall, be it carpet, foam mattress pads, egg cartons, discarded undergarments, banana peels, wide neckties..... is the goal to disrupt the sound waves or to absorb the sound waves? It would seem that the desired result is going to be the biggest determination as to what goes on the walls. Carpeting, while tactile and absorbent, is still a very smooth surface. Egg cartons have those pyramid like shapes to break up the sound waves but they are a hard paper surface.

Keeping in mind that I can't be paying $45 per 2 square feet of proper studio foam panels to be recording my little attempts at writing the next big hit, and that we are not talking about a professional studio where people pay big dollars to record after waiting on a list to buy the time......