Subwoofers

Nice speakers. This one is a no brainer to me as you can get two excellent Rhythmik F12G subs for $1000 less than one of the RELs, and the F12Gs even go significantly deeper as well. I’m sure the RELs are good, but the price differential here is pretty staggering considering that they’ll both likely be excellent in your system/room. JL Audio subs have had reliability issues, so for that reason I’d avoid them given the other solid choices available.  Hope this helps, and best of luck.

Wow, that's a nice large space.  What is your total budget and are you looking for a pair of subs?

my first sub question is always, how do you plan to hook them up and do you plan to highpass? 
 

If you can get past the looks the JTR RS1 the best sub I personally have heard that are not diy monsters. Their lowest low pass setting is 60hz… so keep that in mind if you are not using external controls. I am highpassing mine with a Sublime Acoustics K235.  
 

I am not a fan of Rel. too expensive for round rolled off bass. Their top model are probably fine if you want the looks and have money to spend. My JLs had a lot of failures and I would not recommend the brand. They do sound good though. Rythmic and HSU both look like good buys.