What frequency and Q should be used when trying to model room gain on a program like ported.xls. I am trying to design a sub box with a little hum in the 30-40hz range. I am doing this because my sub will have a fixed crossover of 80hz. My mains have an F3 of 65 so by building a box with a hump at the lower frequencies I will affectively lower the 80hz crossover to the 65hz I need. I don't want to go too far with the hump because of room gain in the lower frequencies.