2014 Sony Nav system speaker output question

Hi all. I'm trying to make a plan for upgrading the abysmal sound quality of my truck, and would really appreciate some guidance with how the system outputs sound to the speakers on a Sony Nav system. It seems like the head unit outputs three amplified tweeter, front door and rear door channels all separately, and then a line level output for the subwoofer to the rear seat amp/sub combo.

My question is are all three non-subwoofer channels full range? Or are there internal crossovers/filters in the head unit sending different signals to each speaker? I've heard conflicting information. I do know there's a capacitor on the tweeter.

Thanks!

i think the bigger issue is the drop of in signal as the volume is increased. Most that upgrade use a sound processor to give a clean and stable signal.

check here it should answer your questions

http://www.fordraptorforum.com/f12/your-raptors-audio-system-37480/