I know you didn't ask this and I don't mean to crap on your subwoofers, but I would not use them in an audio system. They just aren't good enough to do justice to music.
I had one a long time ago and after replacing it with a HSU sub I realized just how bad it was. I also owned a Klipsch Reference Series RW-12d sub. Also crap. I like (some) Klipsch speakers, but making subwoofers is not something they are good at.
If you want to add subs in the mix for two channel audio, flip those Klipsch and get (at least) two entry level SVS, Rythmik, or HSU sealed subs and you'll get much better performance.
I had one a long time ago and after replacing it with a HSU sub I realized just how bad it was. I also owned a Klipsch Reference Series RW-12d sub. Also crap. I like (some) Klipsch speakers, but making subwoofers is not something they are good at.
If you want to add subs in the mix for two channel audio, flip those Klipsch and get (at least) two entry level SVS, Rythmik, or HSU sealed subs and you'll get much better performance.