I just got this HU (Pioneer AVH-P4400BH) and am really looking forward to putting it in using all the great info you guys have posted here.
The 2012 Impreza I have came with all speaker upgrades, including the Tweeters, Door Speakers, and Subwoofer. It uses the Factory CM621UB Head Unit.
The speakers seem fairly decent and I'd like to be able to keep all of them for the new Pioneer HU.
Has anyone had any success or pointers in how to hook up the SubWoofer to the Pioneer? It seems to be a non-amped woofer. The Pioneer instructions say that if you use a 2 Ohm (70W) sub, that you should not hook up the rear speakers and instead use only two wires from those to hook up the Sub. But this doesn't seem right because the factory Head Unit drives both the rear speakers and the Sub.
Is there a way to hook up the Sub from my Pioneer so that I can keep all four door speakers and the sub? I would like to do this without installing an Amp.
Any suggestions or advice are much appreciated!