I have a Channel Master 8 track player I would like to install. How would I be able to do this? There is a DIN socket on the back of the head unit for the CD Changer. IF I can find the wire for it, would I be able to tap into that? Also, the 8 track player is a 13.2 Volt unit, while the car is 12 volt. Where can I find an adapter for that. Thanks!

 

Vehicles rarely run at 12 volts. While running you're going to see 13 to 14 volts depending on what you have turned on and the condition of the battery. You won't need an adapter for the power supply.

The "Channel Master" I looked up seems to have it's own amp. It might have pre-amp outputs you can connect to an external amp and the sub you're asking about in the other thread but it's not going to be compatible with the Volvo stock head unit.