Blending the sub and fronts?

tmorgan Posts: 37
I have a Marantz SR-7200. I have a Polk PSW140 sub(10"185W) and Polk RT800i fronts. I have the sub hooked to the sub out of the 7200 ( all other speakers set to small). The sub out on the 7200 is filtered. The sub has its own adjustable filter. So there are two different low filters, one in the sub and one in the 7200( both active in current setup). Would I be better off running the front speaker cables to the sub and then to the fronts and set the fronts to large( then use the sub crossover to adjust)? Would it be better to use the front pre outs of the 7200 right to the sub line level inputs and set fronts to large(then use the sub crossover)? Would setting the fronts to small filter the front pre outs? This would also keep the sub working in Source Direct mode for stereo listening.
Anybody with similar stuff experiment with any thing like this?
How can I measure the response?
TIA for any and all replys.