So my new head unit only has two pre-amp output ports, however, I am running front door speakers, rear speakers, as well as a sub. I am wiring in 2 amps, a 4 channel to run all the speakers and a single channel to push the sub. Originally I had planned on using the 2 preouts on the head unit to run to the 4 channel amp but then what do I hook the sub amp to? Just a rear speaker high voltage output? Or do I use the preouts for the front speakers to drive all 4 channels on the speaker amp and use the rear preouts to run to the sub amp? The other thought I had is use the front preouts to input for the front speakers on the 4 channel and use the high voltage rear speaker wires for the input for the rear speakers on the 4 channel and then use the rear preout to run to the sub amp. My head unit does have the option to change the rear speaker output for just a sub so that's why I thought it might be a good idea to use the front outputs to input for all 4 channels on ththe speaker amp. Have I confused everyone enough? Thoughts?