after a bit more research it sounds like a 'y' cable won't do the trick for the factory sub and is a bad idea as it might short the outputs on the head unit...
i think i need to run a stereo rca to mono converter to get the factory sub to work, but i'll likely just forget about it and get a powered slimline sub instead.
i think i need to run a stereo rca to mono converter to get the factory sub to work, but i'll likely just forget about it and get a powered slimline sub instead.