I use two 12 inch Goldsound(not Goldwood) 12 inch xmax woofers. They are in a vented 12 inch x 7 feet 6 inch sonotube woofer. The foot print is small, and the difference between a vented design and a sealed design at those low levels is negligible in sound, but much deeper in the bass. They kick! The volume size of each woofer is over 9 cu feet. There is no substitute for volume in the box......NONE!

Marlboro