Bryon, you may find more info if you check
COM_NET and select your coach for Entertainment systems, looking in there you may have the same system I have Sony which you can find info on mine in
QT's 1 & 2 and some of the things I added and what else can be added off the units. Did not see any sub woofer on list.
The link I provided was only for reference and will only give part info of what a system may entail.