Adding sub to factory Infinity system

I searched the fourm but couldnt find a direct answer.
Id like to add a 8 inch sub in the back cubby to enhace the factory set up. Is there any way to wire it to the factory amp or would that be too much of a draw on exsisting amp? Or can I add another amp to power the sub and still keep the factory head unit and amp under the back seat?
I've learned alot about and have done several mods to my xj by reading this fourm, you guys are great! I appreciate any help.

I would Use a seperate amp and sub

forgot what its called but they sell a harness that installs your amp off of the or the infinity basslinkrear factory speaker wires
it senses when power goes to the other speakers and turnos amp off and on and gets audio signal from there as well.
Hook in that way and run your power wire and your good to go

Or the infinity basslink amp and sub in one has it built in As an option.
they can be had on ebay reasonably.

OutkastBoss said:

I would Use a seperate amp and sub

forgot what its called but they sell a harness that installs your amp off of the factory speaker wires
it senses when power goes to the speakers and turns the amp off and on and gets audio signal from there as well.
Hook in that way and run your power wire and your good to go

Or the infinity basslink amp and sub in one has it built in As an option.
they can be had on ebay reasonably.

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fixed it ! Stupid cell phone keyboard

So they sell something that hooks into the rear speaker wire?

Ok this is coming from a former car audio professional.

No you absolutely CANNOT power a small sub off of the factory Infinity amplifier.

Now that we got that out of the way, you can add a sub and amp while maintaining your factory radio. I will add that without upgrading the radio your sound quality will suffer and tuning will be extremely limited.

To get the proper signals from the radio you will need to tap into the factory wire harness behind the radio. THIS IS NOT PLUG AND PLAY! If you do not know what you are doing, do not just go hacking into your radio harness. The best way to tap into the wires is to go down to your local electronics hobbyist store and buy some T-Taps.

The device that will tap into the factory wires and convert the signal into something the amp can use is called a "line-out converter." Here is a good example: http://www.walmart.com/ip/PAC-SNI-35-Adjustable-2-Channel-Line-Out-Converter/21550472

Some amps actually come with this converter pre-installed in the amp itself so make sure to check the amp for this before you go purchase this product.

An amp will also need a big 8-4 gauge power wire and ground wire ran to the amp along with the signal wires.

If you do not have any previous car upgrade experience and are not an avid Do-It-Yourselfer then I recommend taking it to a professional. But if you are like the rest of us here and like to tinker and do things yourself, then do your homework and get in there and do it right! Good Luck!

Ben824 thanks for the info thats the knowledge I was looking for, I just need the factory wireing diagram to see what wires are coming out of the factory unit. Does it matter which wires I tap into for the signal to the sub amp front, back ,left ,right? and will it degrade the signal going to the factory amp?

jeff0862 said:

Ben824 thanks for the info thats the knowledge I was looking for, I just need the factory wireing diagram to see what wires are coming out of the factory unit. Does it matter which wires I tap into for the signal to the sub amp front, back ,left ,right? and will it degrade the signal going to the factory amp?

Click to expand...

What I would do to make it easy on yourself is run down to best buy, buy the factory end harness adapter for installing aftermarket radios. The wires on these harnesses have the universal industry standard colors and markings with labels on them to let you know what the corresponding wires for the factory harness are. This will let you figure out easily which wires are the signal wires for the speakers to tap into.

You will want to pick either front or back speaker wire to tap into. To get the proper signals you will need to tap one right side and one left side speaker wires. Ask you can probably figure out, this is why you would want to pick either front or back. I tend to pick the front since usually the driver balances the fade to the front more so the driver can hear more of the sound. By choosing the front, means if you fade to the front, then you won't pull signal from the sub.

Tapping into the wires doesn't degrade the signal going to the factory amp, or if it does at all then it is negligible. So tap with confidence!

Great can't wait to try it out, have to get a sub and amp first, but its on my list to get done in a week or two. Thanks again!