I have the LFM 1 Compact for my 2.1 computer system. I paired it with my Audioengine 5's. Personally witht he Fathom (model ?), I'm not sure if you're going to hear much from the LFM 1 Compact. Please don't misunderstand me, I think it's a great sub and I'm listening to it right now, but for huge bass, it's only going to give you a limited return with a 10" woofer.
I have the Klipsch RSW-15 and it drops down to 19hz which is nice deep bass. I think you need to look at something with at least a 12" driver, but if you want the low low rumble get an F113 or something with an 18" driver.
I'd read this thread at AVSFrorum
http://www.avsforum.com/avs-vb/showthread.php?t=768150 Fathoms are pretty small subs for the sound they put out. Two should destroy your room adequately.