I am currently attempt in to design a vented 1x15 cab in WinISD, it is my first time using this program and I'm running into some issues. The driver in question is a Celestion BN15-400X and I'm trying to tune at 33Hz. So, the problem is no matter what I do I cannot get the cone excursion below the Xlim of 0.16in at 300W (what my head will put out). At the spike around 57Hz the displacement is 0.375in with my current settings. If anyone could provide any tips, it would be much appreciated.