I have a alpine cda-7840 and I want to use the KCA-801B to connect my carputer to the deck. I read on alpines site that you need a cd changer for the KCA-801B to work, but I also saw on a post somewhere that maybe you just need to wire a 12v remote turn on wire for the deck to use the aux in. I don't want to buy the KCA-801B if its not going to work without a changer. Does anyone here know for SURE if the KCA801B needs a changer to worK?

thanks tons!
-B3AND1P