FunkX

Hey peeps! I have an issue that I can't really even explain, so let me just tell you what I did.

I'll try to spare great details because the first half is just some background. About a month ago I replace the factory Alpine sub with a Polk speaker, and wired up a separate Rockford Fosgate PBR300X2 amp to power the sub. From what I understood I needed to "tap" (not cut) into the front output L/R speaker before/after the factor amp and run that tap to the Rockford Fosgate inputs (L/R). The Rockford Fosgate output was wired up to the factory sub wires next to the factor amp to make it all clean. Now I head back to the factory sub and noticed there were two sets of wires connected. I picked one set and cut the harness and wired it to the Polk - making sure to match the factory from the speaker met the output on the Rockford Fosgate . With everything wired up I could not get the sub to work... Personally I think the amp was a damaged, and so I returned everything and put the stereo back together as previously found.

The Problem:

When I re-connected the sub, using both sets of wires it wouldn't work - no sound, but If I connect only one of the two wires it works. Didn't matter which I connected, nor where on the sub. Both sets of wires (independently) provides sound. Just not when connected together as it was in the OEM configuration. Does anyone know why? Now it seems the sub is under powered... Thoughts? Did I cross a wire or something?

Thanks!

Mattk11

Are you still using the aftermarket woofer but now trying to use the factory amp?

Is your woofer a single voice coil or dual? (Does it have one or two speaker terminals)?

FunkX

Yup, it's all back to the way it was, or should be. Factory AMP and Factory Sub.

Edit: It's a dual - two terminals.

mwtrent

What year is your JK and what system is installed? New JK subs have four voice coils.

Was any wiring done with power going to the sub; if so, it's possible you may have fried a channel in the sub if the sound level has been degraded. I'm assuming the polarity is as it came from the factory. I've used the fade and balance in the past to troubleshoot blown channels.

bombout800

Sounds to me like you damaged the wires when tapping them, or you damaged that channel on the factory amp. Take out the sub and individually hook the coils up to a audio source. You can also flip the wires from one coil to the next and see if the coil that wasn't working and the wires from the coil that was working now make the coil that wasn't working, work. That was you know it's either th wires you tapped or that channel on the factory amp. You could also probe(using a dmm) the wires tApped before the tap and after the tap with the car and headunit off, to see if it's the wires. You should also be able to turn on the headunit and use a dmm to check the voltage output to those wires to se if the amp is actually outputting any power.

bombout800

Pm me if you're confused on anything I said.

FunkX

That kind of makes sense. The taps and all have been removed and the cut sub wires restored. Everything should be as before I ventured down this path - though for sanity I should probably take a triple look.

What confuses me really is the sub works only if only one pair/terminal is connected. For example, and for the sake of simplicity lets call the wires to the dual coils/2 terminals A and B. If I connect A wire to the sub it functions (on either of the terminals), if I connect B wire to the sub it functions (either terminal). If I connect A and B as it was from the factory I get nothing. That's the part that confuses me...

BTW, thanks for the help! I really do appreciate it, and understand conveying this kind of info via a post has it's own challenges.

FunkX

I just took a triple look in a well lit area - outside. I found that i actually had the +/- crossed on one of the sub twist pairs. Had to happened on the rewiring and would explain why the sub was cutting out.

Ok, that's fixed - feeling a little silly over it, and wanted to thank everyone that responded.

bombout800

I figured it was your wiring since the only thing that changed was you tapping it. Although it should have still played, that's another story! Haha glad you got it working