Does anyone know if the rear output are crossed over from the head unit or is it at the speaker itself. I want to use the factory head unit and add an aftermarket amp but don't want to put the chimes though the amp. I was going to add a lineout converter on the rear output and run it to the amp to run all 4 speakers, fade everything to the rear and wire in the left front out of the radio for the chimes to a speaker installed under the dash. I know that will do away with the fade but if it works that's fine so I don't have to amp the left front so the chimes are too loud.