1. what is the resonant freq. ? Im not really all to clear on this subject and I realize I need to understand this in order to understand the qts. And also when the dealer website, say orion for example, says that their sub is best built for a ported box does that mena that they themselves have measured the Qts and that the sub is best suited for a ported enclosure or they are they just saying the sub will perform better as in power handling, lower distortion and all that good stuff?

2.What does it mean for the sub to become unloaded after the cutoff freq. ?