I have the Alpine head unit and amplifier in my 95. When I replace the head unit, do I need a radio with two low level pre-outs? What is the input requirements of the amp? Anyone know the color code of the channels, L/R/Front/Rear going to the amp?

 

If you have the Harmon Kardon premium sound system (CD changer in trunk, 'subwoofer' on rear package shelf) then you will need to accommodate the Alpine M Bus connection to the trunk for the CD changer and the factory harness for the rest of the system connectivity.

There are harness adapters for the non premium system, so you can likely use that as a starting point, and you can get M Bus pinouts pretty readily from a quick Google. I am also fairly certain I've seen the M Bus connector pinout decoded here specifically in a thread or two.

But you definitely can install an aftermarket unit without having to cut into the stock harness, although it may take a little detective work if you want to maintain the stock CD changer and amplifier.

Ideally you could probably put in an Alpine unit and save a lot of headache a I 'think' the M Bus will work directly, or if you have an Ai Net changer you'll need an M Bus -> Ai Net converter which is also readily available. I haven't tried that myself, but I've read some posts here and on BMW sites that have a similar HK setup and folks retrofit aftermarket Alpine head units and later model CD changers.

I'd do a quick search for "radio" here and Google for "Harmon Kardon CD changer", etc and then just wade through the posts.

I have to say as an aside though that the stock premium system sounds pretty darned good to me when it is in good working order. I put a pretty nice system based on Rockford Fosgate and Kenwood amplifiers, with DLS speakers in my 95 Riviera and while it does sound 'better'.... it really only sounds better REALLY loud, and that's where the HK system in the XJR peters out a bit at ear deafening loudness

I don't like to listen at that sound level anymore, so I'm pretty pleased with the quality of the reproduction on the HK system, especially with a good CD. I still have to pull my head unit and send it off for repair as it has intermittent problems that I know how to 'work around' for now. But it really needs to get fixed.

Good luck. I'm sure you can find all the info you need here after an hour or so of compiling the posts from old threads.

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Al,
Thanks for the info. I plan to put in a Kenwood, that has the pre-outs I need, but what I was looking for was the input sensitivity for the amp? The Kenwood has 4V pre-out and I did not want to overdrive the amp, if it has only 2 or 2.5 v inputs?

Thanks

Jeff