CD Changer PLUG to iPod?
 

I have a friend, who has helped me many times, that asked me for help today. Idk what he drives, (I've only talked to him online for the last couple of years), but I know this question can be very universal.

He has a cassette player up front. He doesn't want to go the cassette adapter route because of quality (I told him it was poor quality).

He has a plug in the trunk for a CD Changer. I assume it's something like the image I attached. He wants to know if there's any way he can run this plug to an iPod. Car audio isn't my strong point, but I thought about one thing, although idk if this has both inputs and outputs or not:

One of those RCA audio converters that connects to the cables that run into the head unit and converts it into RCA ports? I've never seen one in person, but I assume they're powered and everything? If he got that and ran his iPod to that, would it work? And would it sound better than the whole "Cassette adapter" thing?

Basically, he needs something that's like an isolated version of the PART of the headunit that takes in audio, (Aux port), and it has to be powered and everything.

Or maybe some kind of FM transmitter that works well with the iPod? Whatever has the best sound quality.

pac-audio.com or usaspec.com have vehicle specific ipod interfaces that provide audio input and ipod charging.

cassette adapters are pretty low quality, as are FM modulators. a direct input through a factory CD changer input, SAT radio input, etc. is doable for some cars.

it totally depends on the year/make/model/trim.