JL Audio e112 sub vs. JL Audio Fathom 112 v.2

I think I misled everyone:  the volume of the e112 is turned up about 3/4 of the way, rather than all the way up.  (I am fairly certain that the sub is behaving properly because after receiving it from the dealer I sent it back to get it checked out, and it was fine.  My listening room size is 23 feet (length) X 12.5 feet (width) X 8 feet (height). 

James, I have custom-built Audience Wavemaster D-class monoblocks which are pretty powerful.  Please excuse my ignorance, but what are "mains"?  It would, of course, be less expensive for me to buy a second e112 than a new Fathom 112.v2, so if that would work well that sounds like a grand idea.  Glenn

Now I am totally confused.  Sorry to be dumb....but I don't understand what either dweller or willand is saying.