I have not been into dyi audio since the mid 90's and the Speaker Design CookBook. After finding this great forum and WINISD Ive been trying to tutor myself on the program and refresh myself on speaker design. I picked a simple speaker in the directory to work with for my tutorial, the Focal 33wx. Vented box per Focal spec sheet with a 35L box, 10cm-30cm port, fb42HZ entered in several alignments gives me port velocity in the mid 20's around 40hz with a 200w signal. The cone excursion is well within the limits at 30hz and above. With a 400w signal, the Focal nominal power rating, the cone excursion is still within its limits at 33hz and above but the port velocity is off the chart. Am I missing something or entering something wrong. Thanks