JL Audio

I am working on an upgrade to my theater and was curious on people's thoughts on what configuration makes the most sense.

My room size is 13' x 21' and I hope to match up the sub with a set of B&W CM9's.

Should I go with one F113 or two F110's? Pros/Cons
I use two JL f110's for my stereo where they play in the background to fill in the sound. I had one f113 in my room, but for better imaging and the small roll they play in my 11x25 foot room the f110 (for the price) is all I need.
For home theater where a sub plays a larger part you need the f113 for better impact and to shake the walls.
Music get one 112
Movies do the 113
Depends what you listen to.

The 110 doesn't have enough punch.
That is just my 2c ymmv.
I use two F113's. The point is not to shake the walls but to even out the frequency response in the room (always easier with two subs). I would buy one F113 now and when funds become available buy the second one later. You can run them in stereo (master/master) or as master/slave (which I do).

By the way, if the walls are shaking and you are not watching the pod scene in War of the Worlds you are running them way too hot and/or you have room mode issues to fix.
One F113 will be better for HT than dual F110. The one
F113 will go lower with more clean output!
I have 2 x f113 in an identically sized room. Walls are not shacking at all. Just clean tight bass. Get one f113 first, and when funds permit get a second and run as discrete stereo pair. Always nice to know there is an upgrade path down the road. Getting 2 x f110, be done with it and always wonder what 2 x f113 would have been like is plain audiophile torture IMO.
I have the F110 and would recommend 1-F113
I have one JL-F113 and an extremely satisfied with both music and movies. My Arcam FMJ-888 has a built in eq and speaker set up. After running this I no longer have the walls shaking but excellent balanced low end. I did do some tweaking to the sub. I had Bright Star Audio create a stand about 12" high that I filled with sand. That alone made the sub more musical IMHO. I then upgraded to a Synergistic Research Subwoofer 2 XLR Cable. OMG that cable mellowed out the boom and now I am extremely happy with my investment and choice. One is enough if you assist it just a little. My two cents.
Sailcappy makes a good point about how a cable can take a sub from good to great. When I added the Synergistic Subwoofer 2 XLR cable to my system, it was as if my JL-F112 took singing lessons.
Tried the f110(not enough) and the f112 (enough). Friend had a Velodyne Optimum 12 and brought it over. A/B'd the two and the Velodyne actually sounded tighter and more powerfull. Have since returned f112 and purchased Optimum 12. Saved almost $2,000. I strongly suggest you find a shop that will let you demo numerous subwoofers before purchase. All rooms have different acoustics. JL is very good but in my belief it is overpriced.
Just purchased a f113 and have been listening over the last 24 hrs so still adjusting but at this point I can say it is very, very, very quick, accurate, muscular only when called for plus it has a sense of effortlessness in power (so that's what 2500 watts of power does!). I'm not into home theater but I had the pleasure of visiting Dr Bill Gaw last week who has 2 of these subs in his room and when we watch the gladiator scene of GLADIATOR my palms actually were sweating! It was a wow experience. The JL Audio f113 has put my 2 REL Stentors to bed, may they rest in peace (and for the love of me why couldn't REL have placed all controls on the front of the box!).
(Dealer disclaimer)