I currently have Infinity 6 1/2's in Door and 3-way 6x9's in back. I just bought Polk C400.4 amp and Polk 12" MoMo single coil sub. I was wondering how I could wire system so that all 4 speakers & subwoofer were getting power. Thanks!
id get a decent mono amp for the sub but until then you could run the 6x9s off the hu, the 6.5s off the amps front channels and bridge the rear channels for the sub.
You shouldn't even bother hooking those 6X9s up unless you want rear fill. Running those speakers would only mess up the sound you have up front. NiteScort had the right idea.