I've done much searching around the forum regarding how to add subwoofers to my XJR. I have installed an aftermarket single-din deck to get iPod connectivity and to add subs. However, after reading a post by Grandell about a cord connection that plugs right into the CD changer to get iPod connectivity, I'm rethinking my system.

Even though I'm happy with how the install of my single-din came out, I must agree with other members that it still doesn't look right. I would like to reinstall the factory headunit and CD changer and use the cord that Grandell talked about. I'd rather have the stock look than the ugly single-din, even if it is better than stock.

My question is if I were to reinstall everything and use the iPod cord from the CD changer, would I still be able to hook up and aftermarket bass amp and subwoofers? I have the premium Harmon-Kardon system, but the factory sub has been removed(it was blown).

Any thoughts?

EDIT: Here is the post that Grandell spoke of -https://www.jaguarforums.com/forum/xj-x308-xj8-xjr-27/what-did-you-do-your-x308-today-84298/page29/#post939662

 

Don't give me too much credit, JaguaXJR was the one that mentioned the adaptor in the first place.
You should be able to use the plug that goes into the factory amp to connect an aftermarket amp, but it may get a little bit tricky as there is no dedicated sub output, only front/back left/right. The factory amp combines the front left and right signals and feeds these to the sub, after the relevant filtering for sub frequencies. It's not hard to achieve the same result with aftermarket amps though.
What I would really love to know is whether the premium headunit puts out a line level signal, or if it's a high level signal like the regular headunit.

 

if you want to replace the sub I've got a brand new Pioneer 6x9 I could send you (or drop off on our way to SLO over Mothers Day). I've got the other in my rear deck and it works just fine - not GREAT - but fine. Plus that trunk is sealed VERY well so you'll want something in the "sub" location

 

I've been reading that you could use the wires going to the factory sub and run those to an aftermarket amp. Is that possible? Or would splicing need to be done? I'll be honest, I don't know enough about audio wiring to tell if its a line level signal or a high level signal.

Mcm97: Thank you for the offer, however I already have 2 12" in a box that I'm currently using. They work very well at the moment. I installed them because I wanted more bass, more than what a 6x9 could do. Thank you again.

 

Sorry, I didn't quite get my wording right before, was a little distracted at A&E with an injured partner. She injured her ankle at indoor soccer. Who says exercise is good for you...

Out of the factory headunit there are 6 wires. One common ground for all channels, 4 channels of sound (FL, FR, RL, RR), and the last must be a signal to turn the amp on.
These 4 signals are sent to the amp, where the front left and front right are split up 3 ways each. High frequencies go to the tweeter, mids go to the door speaker, and bass goes to the sub.
So the sub gets TWO feeds from the amp, one left and one right, which go into seperate voice coils on the sub. I believe the factory 6x9 'sub' has two 2ohm voice coils.
The main result is that you get nice even bass, even if your music is moving around left to right on the main speakers.

To run an aftermarket sub you have two choices, you can use these amped feeds, or you can intersect the signal before it gets to the amp.

If you're using the feed out of the amp, you will need to either use an amp that will take high level imputs, or use a line level converter with RCA outputs. If you use the original signal from the headunit then you can upgrade your amp as well, and if you're lucky, your amp will have an RCA output, that you can use to feed a sub amp.

However, you will still have the issue of having a left and right signal. You really just want a mono signal for a sub amp, so you could possibly use an RCA joiner (like a splitter, but in reverse), or you could run two channels of amplification and run dual voice coil sub(s).
I don't have this situation, as I am running a stereo signal into an aftermarket processor.

If anyone would like to run their ideas past me I would be happy to offer as much advice as I can. It's a bit hard to cover every option with a generalised answer, as everyone tends to want different things.

 

First off, I hope she's okay. I have a sister who got involved in a soccer injury, but it was a head injury. Nothing serious.

So, the subs I have no are dual voice coil. The bass amp I have now is a mono block. For now I plan on using the factory amp to power everything. So would I still use the RCA joiner along with the converter to power the subs?

 

I would think so. It would pay to talk to a proper car audio professional, just to make sure there won't be any complications joining the left and right sub channel together, but it should be ok.
I'll ask around a few people I know and see if they have a definitive answer as well.

Actually, now that I think about it, you'll probably find you have two RCA inputs on your amp, which are actually bridged to create a mono input.
So you'll take the high level output from the factory amp, run that into a line level converter, then run a pair of RCAs from the output of that, into the amp, and run your amp like normal.

The only other issue I can see is that the crossover point for the sub is fixed by the factory amp, so you will have an upper limit on which frequencies your sub will play. I doubt that will be much of an issue though.

 

I'm going to give that a go then after I reinstall the factory equipement. Thanks a lot for your help here, I appreciate it!