Running Sunfire Sub and Tube Amp

I'm starting a system with integrated tube amp, like Cayin 88T with my Paradigm Studio 60s v.2. I also have a Sunfire HRS-10 subwoofer available and think it might go well with the Studio 60s. Since integrated tube amps don't have preamp outputs for a sub would I route the speaker outputs thru the Sunfire for crossover? Will this degrade the sound to the speakers? Is it worth it?
That is how you should hook it up. From what I've read, using the speaker level inputs allows the flavor of the main amp to come through the sub amp, and thus makes it easier to blend the sub to the main speakers. Makes since to me? Anyway just try it and see how it sounds. Good Luck!
I run a seperate pair of speaker cables to the mains and to the sub. This way the sub doesn't get involved with the mains. You don't have to run very expencive wires to the sub but at least some 14awg ox free copper. Its like bi-wiring but instead of two runs to the mains its one to the mains and one to the sub. Hope this helps.