On this new USA '07 2.5i MT5 Wagon, I intend to replace the head unit with an Alpine 9856 or Pioneer 4800/5800, both of which are available with dedicated subwoofer output and control. I'm hoping that this approach will provide a stereo sub signal condensed safely into a mono output for the single factory OEM sub my car came with. I know bass is generally not panned strongly to the right or left channel, but in rare cases it is.
Does someone have a moment to answer these few questions?
1. Will a speaker-level output be sufficient to run the OEM Subwoofer?
2. Some owners with aftermarket head units that have no dedicated sub outputs just tap off of one of the main speaker outs to run the sub, is that still a sensible alternative?
3. The factory radio seems to tap off a front speaker output. Is that true? Would that be just one, left or right, rather than some combination of both? I think some combination might cause an inappropriate right/left signal cross.
4. One owner tapped off the front left for his subwoofer output. Was that a good choice?
Thank you for your time and expertise. This forum is great and I've already learned a lot from everyone!