Anyone ever try to bridge the Alpine sub outputs to mono?

[Neil Derryberry]

I've got a 2016 2500 CC with the 9-speaker Alpine system. I've also got a Pioneer mono 10" sub that needs a home. Has anyone ever tried to bridge the left/right sub channels together to feed a mono sub?

 

[corneileous]

If you’re going to be using your own amp- which I would highly recommend, I don’t think it would matter.


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[Neil Derryberry]

If you’re going to be using your own amp- which I would highly recommend, I don’t think it would matter.


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That wasn't the plan.. my hope is to use what's already there. If I end up having to bring a new amp into the mix I'll use the sub out from what's already available on the aftermarket head unit. Going for $0 here..

 

[corneileous]

That wasn't the plan.. my hope is to use what's already there. If I end up having to bring a new amp into the mix I'll use the sub out from what's already available on the aftermarket head unit. Going for $0 here..

I highly doubt you’re gonna like the results if you do it that way. The amp that will power that 10 inch sub of yours is the same amp that powers all the other speakers in your truck. Plus it’s got a pretty strict protection circuit in it as well.

Before I bought my dual-10 inch JL audio stealth box and JL Audio 500 watt amp, I had tried a Pioneer 8 inch sub that hooks up the same way the factory subwoofer does and even though the new sub seemed like it had just a little bit more of a punch to it, you also couldn’t hear it at the same time as it was a lot quieter than the factory sub. I mean, it was literally like you had installed a volume knob for that circuit and then turned the volume down to a low level with that new pioneer sub- which yes, I didn’t do that, I’m just using that as an example to describe how much quieter the sound was because obviously that new speaker required a whole lot more power than the factory one did.

But yeah, I guess to answer your question, those two twisted together pairs of wires that come out of the carpet- see pic below, I don’t know if that’s actually a left and a right or not.


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[BWL]

I'm lost. The alpine system has only 1 sub and is mono so what is there to bridge to mono.All you can do is replace the sub with a different one and run it off the factory amplifier.

 

[corneileous]

I'm lost. The alpine system has only 1 sub and is mono so what is there to bridge to mono.All you can do is replace the sub with a different one and run it off the factory amplifier.

If it’s mono then why is there two sets of wires that connect to the factory sub?


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[BWL]

If it’s mono then why is there two sets of wires that connect to the factory sub?


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Can you explain how to get stereo sound from 1 speaker? I've done a little digging. The factory sub is a 2ohm dvc and is powered from 2 seperate channels, but still mono output of the factory amp. The factory amp is not designed to run 2ohm bridged, but a 4ohm should technically be ok given most stereo amps minimum ohm load doubles when bridged. I wouldn't risk it though.Just buy an amp, live with the factory offering or try a 2ohm dvc replacement sub. Technically your Jl amp could get it's signal from either one of the pairs of wires and you technically have the amp bridged, but the load for line level input is pretty low.

 

[corneileous]

Can you explain how to get stereo sound from 1 speaker? I've done a little digging. The factory sub is a 2ohm dvc and is powered from 2 seperate channels, but still mono output of the factory amp. The factory amp is not designed to run 2ohm bridged, but a 4ohm should technically be ok given most stereo amps minimum ohm load doubles when bridged. I wouldn't risk it though.Just buy an amp, live with the factory offering or try a 2ohm dvc replacement sub. Technically your Jl amp could get it's signal from either one of the pairs of wires and you technically have the amp bridged, but the load for line level input is pretty low.

What are these two separate channels? And where did you get your information, I’d like to read up on this too just in case there could be a little bit better way to hook the signal feed up to my amp which is basically all I did was take the short wiring harness out of the factory speaker box, plug the one end to the connector where the box connects to the wiring harness and then took two of those Ram-specific Mantra brand wiring connectors and took some JL Audio RCA adapters, wired them to the bare wire ends of the mantra adapters and just took a simple RCA cable and plugged in between those wires and the RCA-jacked input of the amp.

But if those two pairs of wires that come out of the carpet for the factory sub aren’t a left and a right then what are they?? I’m assuming that last part you’re talking to me so what do you mean when you say I could use just one pair of those twisted-together wires?


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[BWL]

What are these two separate channels? And where did you get your information, I’d like to read up on this too just in case there could be a little bit better way to hook the signal feed up to my amp which is basically all I did was take the short wiring harness out of the factory speaker box, plug the one end to the connector where the box connects to the wiring harness and then took two of those Ram-specific Mantra brand wiring connectors and took some JL Audio RCA adapters, wired them to the bare wire ends of the mantra adapters and just took a simple RCA cable and plugged in between those wires and the RCA-jacked input of the amp.

But if those two pairs of wires that come out of the carpet for the factory sub aren’t a left and a right then what are they?? I’m assuming that last part you’re talking to me so what do you mean when you say I could use just one pair of those twisted-together wires?


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If you were to pop out your factory sub you'd see that there's 2 positive and 2 neg terminals on it. That's because it's a dual voice coil sub, but unlike a more normal wiring set up where a dual 2 ohm sub would be wired parallel for 1 ohm or series for 4 ohm they run a seperate amp channel for each voice coil keeping it 2ohm. Also why the shallow mount pioneer sub recomended for replacement is a 2ohm dvc. Both channels have the same signal and output since they both run the same speaker, just different voice coils. Between crutchfield, other forums and the old sub box I pieced it together. Putting the wires together is the equivalent of hooking both positives together and both negatives together on a 2 channel amp to combine the power for 1 channel. If you twisted those wires apart 1 of the positives and 1 of the negatives would still give you line level output, but you'd have to adjust your amp gain for the lower power signal as long as you find the positive and negative from the same channel. How you have it should be ok and given there's been no issues so far I would leave it alone. Hooking up a speaker that way however means a lot more load on the amp than just picking up an audio signal. If you look at most 2 channel amp spec sheets you'll see the max load in stereo is twice the allowable vs bridged to 1 channel so I can only take a guess that the same is true in this case, but getting a spec sheet for a factory amp. Well I couldn't find one, so I can't be sure.

 

[corneileous]

If you were to pop out your factory sub you'd see that there's 2 positive and 2 neg terminals on it. That's because it's a dual voice coil sub, but unlike a more normal wiring set up where a dual 2 ohm sub would be wired parallel for 1 ohm or series for 4 ohm they run a seperate amp channel for each voice coil keeping it 2ohm. Also why the shallow mount pioneer sub recomended for replacement is a 2ohm dvc. Both channels have the same signal and output since they both run the same speaker, just different voice coils. Between crutchfield, other forums and the old sub box I pieced it together. Putting the wires together is the equivalent of hooking both positives together and both negatives together on a 2 channel amp to combine the power for 1 channel. If you twisted those wires apart 1 of the positives and 1 of the negatives would still give you line level output, but you'd have to adjust your amp gain for the lower power signal as long as you find the positive and negative from the same channel. How you have it should be ok and given there's been no issues so far I would leave it alone. Hooking up a speaker that way however means a lot more load on the amp than just picking up an audio signal. If you look at most 2 channel amp spec sheets you'll see the max load in stereo is twice the allowable vs bridged to 1 channel so I can only take a guess that the same is true in this case, but getting a spec sheet for a factory amp. Well I couldn't find one, so I can't be sure.

Ok so, lemmie get this straight- those two wiring harnesses in the first picture below that I’m holding in my hand; those are the two mantra connectors that you can buy pretty much at any car audio supply store that are plugged into the two connectors that used to be plugged into the original sub.

But anywho, as you can see in that same pic, the red and black wire and and the other speaker wire that has the transparent insulation, those are the two wires that go all the way over to my amp that have the genuine JL Audio RCA adapters wired on the ends of those wires that attach to the amp.

On to the second pic, the wire harness that had half of it outside the factory box and half of it inside the factory box, those are one pair white and black and the other pair is black and white. I’m assuming the black wires are negative and the white wires are positive?

But on to what you were saying about it supposedly being ok to have it wired that way, I’m intrigued about what you said about putting extra load on the amp; my system works, but ive noticed that I can’t really run my system with the motor off because of I’m assuming the battery input voltage safety. It’s far from running the battery down, but the amp shuts down when the engine isn’t running and the bass hits really hard.

Is it possible I may just only need to take the two white wires and the two black wires, like you were saying, and bridge them to the amp, or just use one of those wires?

I guess I just still don’t understand what the proper way to use that amp with two sets of speaker wires coming from the factory amp for a dual voice coil speaker.





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[BWL]

You should only need 2 of the 4 wires, but it has to be 1 positive and 1 negative from the same channel. If you can figure out which pair went to which voice coil originally you only need to hook up 1 pair from 1 voice coil. I don't know what colour is for what so easiest would be to pop open the oe box and see which pair runs to which coil. The other pair should just be terminated so they don't touch each other or ground out, but they should not be needed. It looks like you have pos and neg seperated already so I guess if you just take a wire out of each pair and it doesn't work just switch which negative is connected. Looking at your adapters you likely just need one of them and leave the other disconnected.

 

[corneileous]

You should only need 2 of the 4 wires, but it has to be 1 positive and 1 negative from the same channel. If you can figure out which pair went to which voice coil originally you only need to hook up 1 pair from 1 voice coil. I don't know what colour is for what so easiest would be to pop open the oe box and see which pair runs to which coil. The other pair should just be terminated so they don't touch each other or ground out, but they should not be needed. It looks like you have pos and neg seperated already so I guess if you just take a wire out of each pair and it doesn't work just switch which negative is connected. Looking at your adapters you likely just need one of them and leave the other disconnected.

As you can see in the picture indicated by the red arrow, there’s at least a green and grey colored wire both with a white tracer but I can’t see the other wires below that. Those are the wires that lead to the connector that the harness that’s attached to the factory subwoofer box plugs into. On the subwoofer side of that 4-wire plug, they are two black wires and two white wires. On the truck side of that connector, there’s at least the green with white tracer and the grey with white tracer but I don’t know what color the other two wires are.

But it’s interesting about what you say about only needing one of those wires but does it really matter which one is what? Are you expecting me to believe that each one of those factory sub boxes that come to the factory, come with a specific harness on the inside hooked to a specific side of the sub? You would think that if both connectors were specific to which port they plug into on the speaker that each of the two plugs would be unique to each other because ****, the day that I tried that pioneer direct replacement speaker that I got from crutchfield before I decided to try the stealthbox, I unhooked both connectors from the factory speaker, took it out and used the two mantra adapters I bought and just hooked each connector to which ever side of the speaker with no regard of where they went- and once I figured I wasn’t crazy about the sound and reconnected the factory speaker back in, it’s anybody’s guess if the harness clipped back to their original locations on the speaker because as I said, they’re exactly identical to each other.

I wonder if crutchfield might know this stuff. I might call them up tomorrow and run this by them.




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[BWL]

As you can see in the picture indicated by the red arrow, there’s at least a green and grey colored wire both with a white tracer but I can’t see the other wires below that. Those are the wires that lead to the connector that the harness that’s attached to the factory subwoofer box plugs into. On the subwoofer side of that 4-wire plug, they are two black wires and two white wires. On the truck side of that connector, there’s at least the green with white tracer and the grey with white tracer but I don’t know what color the other two wires are.

But it’s interesting about what you say about only needing one of those wires but does it really matter which one is what? Are you expecting me to believe that each one of those factory sub boxes that come to the factory, come with a specific harness on the inside hooked to a specific side of the sub? You would think that if both connectors were specific to which port they plug into on the speaker that each of the two plugs would be unique to each other because ****, the day that I tried that pioneer direct replacement speaker that I got from crutchfield before I decided to try the stealthbox, I unhooked both connectors from the factory speaker, took it out and used the two mantra adapters I bought and just hooked each connector to which ever side of the speaker with no regard of where they went- and once I figured I wasn’t crazy about the sound and reconnected the factory speaker back in, it’s anybody’s guess if the harness clipped back to their original locations on the speaker because as I said, they’re exactly identical to each other.

I wonder if crutchfield might know this stuff. I might call them up tomorrow and run this by them.




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Both harness adapters for the factory sub do the exact same thing so reversing them doesn't matter. You should just have to use either one of them for line level. Not both.

 

[corneileous]

Both harness adapters for the factory sub do the exact same thing so reversing them doesn't matter. You should just have to use either one of them for line level. Not both.

Ok well, I decided to go out to the truck and take some more pics- this is the main 4-wire plug that the factory sub assembly connects to.

In the second picture, the wire on the far right which is the grey with I’m assuming a brown tracer, goes directly to the top white wire in the first pic.

Working in that direction- right to left in the bottom pic and from top to bottom in the first pic, that’s where the wires go to and since it’s kinda hard to see in the second picture, going 1. 2. 3. 4., 4 being on the right and 1 being on the left, 1 is green with white tracer; 2, is grey with white tracer; 3, green with brown tracer and 4, grey with brown tracer.

But anywho, if I choose just one of these wire pairs to run to my amp,
What will change? What will I have to change on my amp settings? Should this cure my amp seeming like its working itself too hard and maybe if I just use one, you think this would let my amp run when the bass hits when the ignition isn’t running?





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[Cableman]

Ok so, lemmie get this straight- those two wiring harnesses in the first picture below that I’m holding in my hand; those are the two mantra connectors that you can buy pretty much at any car audio supply store that are plugged into the two connectors that used to be plugged into the original sub.

But anywho, as you can see in that same pic, the red and black wire and and the other speaker wire that has the transparent insulation, those are the two wires that go all the way over to my amp that have the genuine JL Audio RCA adapters wired on the ends of those wires that attach to the amp.

On to the second pic, the wire harness that had half of it outside the factory box and half of it inside the factory box, those are one pair white and black and the other pair is black and white. I’m assuming the black wires are negative and the white wires are positive?

But on to what you were saying about it supposedly being ok to have it wired that way, I’m intrigued about what you said about putting extra load on the amp; my system works, but ive noticed that I can’t really run my system with the motor off because of I’m assuming the battery input voltage safety. It’s far from running the battery down, but the amp shuts down when the engine isn’t running and the bass hits really hard.

Is it possible I may just only need to take the two white wires and the two black wires, like you were saying, and bridge them to the amp, or just use one of those wires?

I guess I just still don’t understand what the proper way to use that amp with two sets of speaker wires coming from the factory amp for a dual voice coil speaker.





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The 4 factory wires are just a neg and a positive from the source and feeding each voice coil with 2 ohms, those adaptors should be fine as the center of an rca is a positive and the outer edge is the negative for each pair.
Only other thing is can the amp you have handle the highlevel input?
I read on here alot aren't happy grabbing signal from the sub location or any where with the factory alpine amp.
Not sure how correct i am lol but im leaning towards the amppro setup for adding my amp and sub combo.

 

[corneileous]

The 4 factory wires are just a neg and a positive from the source and feeding each voice coil with 2 ohms, those adaptors should be fine as the center of an rca is a positive and the outer edge is the negative for each pair.

So you’re saying I’m fine to use both? Or just one?

Only other thing is can the amp you have handle the highlevel input?

It’ll handle up to 8 volts.

I read on here alot aren't happy grabbing signal from the sub location or any where with the factory alpine amp.
Not sure how correct i am lol but im leaning towards the amppro setup for adding my amp and sub combo.

My take on that, a lot of people who I guess want the most out of their amp and subs which means they want to completely bypass the protection of the factory amp, are the ones who go to the trouble to rip their dash apart to install something like this or equivalent. I could probably go that way with my stealth box but lemmie tell ya, even on my factory system, I’ve got more bass than I know what to do with except for the fact that in my old truck- which, I’m not sure if you’re familiar with them or not but I had one of those amplified and loaded with 10” subs MTX Thunderform enclosures that didn’t put out quite the bass as my new system but I could at least run that straight off the battery for a while with no interruptions. This Stealbox system with this JL Audio Amp, that’s made for the stealthbox on the other hand, within the very first really mega bass hit, the system shuts itself off from I’m assuming to low input voltage through the big red cable attached to the positive on the battery. It doesn’t do this when idling.


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[BWL]

Ok well, I decided to go out to the truck and take some more pics- this is the main 4-wire plug that the factory sub assembly connects to.

In the second picture, the wire on the far right which is the grey with I’m assuming a brown tracer, goes directly to the top white wire in the first pic.

Working in that direction- right to left in the bottom pic and from top to bottom in the first pic, that’s where the wires go to and since it’s kinda hard to see in the second picture, going 1. 2. 3. 4., 4 being on the right and 1 being on the left, 1 is green with white tracer; 2, is grey with white tracer; 3, green with brown tracer and 4, grey with brown tracer.

But anywho, if I choose just one of these wire pairs to run to my amp,
What will change? What will I have to change on my amp settings? Should this cure my amp seeming like its working itself too hard and maybe if I just use one, you think this would let my amp run when the bass hits when the ignition isn’t running?





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Try it with just 1 pair. Only adhustment you may change is the gain control. Everything else would stay the same setting wise. It may cure your issue.

 

[Cableman]

Yeah you could try it with just one rca connected but i dont think that will stop it.

Connect a dvm to the amp positive/neg and set the dvm to min if you can, crank your system with battery off and see what your battery drops too.

I had a 3 way jl audio amp in my 2008, it did the same thing yours is doing but only with truck running, turns out the factory regulator in the pcm was spiking my voltage over 16vdc and shutting amp off.

You may have a bad battery actually since its not running and fine when it is running.

 

[corneileous]

Yeah you could try it with just one rca connected but i dont think that will stop it.

Connect a dvm to the amp positive/neg and set the dvm to min if you can, crank your system with battery off and see what your battery drops too.

I had a 3 way jl audio amp in my 2008, it did the same thing yours is doing but only with truck running, turns out the factory regulator in the pcm was spiking my voltage over 16vdc and shutting amp off.

You may have a bad battery actually since its not running and fine when it is running.

I don’t think it’s a bad regulator or battery; the truck’s only less than three years old.


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[bigred90gt]

I don’t think it’s a bad regulator or battery; the truck’s only bless the am three years old.


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My OEM battery (in my 17) went out at a bit less than 3 years, so it could possibly be the battery.