Ok, when building a bass cabinet and looking for the right speaker, what is the MAIN thing you look for? I know weight is a big issue with me. I've been looking heavily into the new celestion bn10-200x and bn10-300x speakers. However, the Fs that a celestion rep gave me seems sort of high. Isn't that the best frequency for the a speaker to resonate at? I'm not exactly sure. The bn10-200x has an Fs of 65 Hz with a recommended 1.09 cubic ft per speaker. So how could I build a box for one of these or a set of 4 10s that could handle a low E beautifully? maybe a B?