I posted this last night on another thread...
I had the Lava about 2 years ago. It was my first subwoofer purchase for HT in more than a decade. At the time, i was very limited as to what I could buy financially. There were many skeptics as to its performance, but one member on here who is pretty well respected (I think it was Counsil) gave it a pretty good review. That coupled with the fact that I was willing to give my money to a new company trying to break into a otherwise crowded market was what sealed it for me. While I had nothing to compare it to, I found it to be a good sub for HT for everyday use, ESPECIALLY for the money, and PROVIDED you weren't looking for a flat response below 25hz and crazy output. FWIW, I did register 95db on a 24hz test tone from my LP which was about 7 feet from the sub. The other thing that I noticed, was that I never experienced port chuffing no matter how loud I wanted to go, it just didnt get any louder. I ended up getting another so I had co-located duals for under $600.
I since upgraded to an Empire (which was BIG, and very good sub, and then upgraded again to a passive JTR Captivator (which is on another level all together) so I clearly understand now what a true HT sub with crazy output is. That said, while I have never heard the Klipsch, I dont think you will be unhappy with the Lava. Post up when you get yours.
(End other thread)
Like others have said, you won't find anything close to the output ability of the Empire for 600 bucks. So again, what volume setting is the Empire set at? Did you try figuring out if you have a room issue? I forget, how big is your room??