I've been playing around with WinISD pro to see what I can do with the two drivers (ACI SV12 and DV12) I have. I've been puting them in vented boxes in the software because I want to get as much low end extension as possible (F3 at 20Hz or below). What confuses me is the linear excursion predicted by WinISD exceeds the Xmax at 20W of input power? I wouldn't expect that to occur since these drivers are rated at over 100W. I guess I don't understand something about the significance of the excursion plot, the power input in WinISD, or how much power the driver actually sees. Could somebody please explain this to me? Thank you!