Thanks for the explanation on the port calculating. I still don't think I fully understand. So is the 30-40 square inches the actual port opening (heightxwidth) for example 12"x3"? Or is the 30-40 square inches the total port area (heightxwidthxlength) for example 12"x3"x24"? I just made these numbers up off the top of my head so I know they may not be correct. Like I said I still don't quite understand how to calculate the port dimensions. If you could help me out I would greatly appreciate it. I am looking at 2.5 cu.ft. with a port tuning of 33hz as recommended in the pinned section at the top. If say I wanted the port to be 12" tall and 3" wide how long does it need to be? Also this is for a square slot port.