Although an 8 inch port would be optimum, you can use a 6 inch port as well. With a total lengrh of 19 inches, it will tune the box to 18 hz. With an input power of 800 watts, a high pass filter would be required at 16 hz to control over excursion of the sub.
After I first unpacked and dialed in my SVS-PB2000, I started up Tron Legacy and skipped to the light cycle battle. I had watched this scene plenty of times to test out other cheaper subs like my Onkyo SKW-580, Polk PSW505 and Klipsch sub-12hg. This time I actually felt the bass. The Klipsch was great at getting pretty low but the SVS was like a shockwave pounding you in the chest. This was all confirmed by my wife who ran into the theater yelling at me about how it sounded like a bunch of tanks were rolling down the street. Next on the list is the SVS PB-4000.