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I have been into basic audio home and auto forever but never anything advance. Can't afford to experiment but no dummy either. I do understand wiring basics ohms, watts, and different wiring parallel/ series. But never strapped or daisy chained amps to run one dvc 2ohm sub. Blah, blah, blah sorry! I have two identical Dual XPR82D amps that I want to combine for double output to one Kicker compR 12" 2ohm dvc sub. The amps don't have a master or slave setting but in the manual it states that they have full settings on the crossovers so you can link [LINK] them for double output. They have RCA inputs and outputs but no instructions anywhere on earth on how to accomplish it correctly. Especially when you are powering one dvc sub. I have distribution block and everything I need except the knowledge and confidence to try it. Any help whatsoever would be great and I would learn something which is why I am here. Thanks!
 

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Ok so how can I utilize the two amps for the dvc sub for best output? They have RCA outputs for daisy chaining or am I mistaken? I definitely could be mistaken that's why I am here. By the way thank you for your time and reply!
 

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By the way the amps are 2ch 2x 120 at 2 ohm or bridged 240x1 at 4ohm . Should I just run them bridged to each vc separate except RCA plugs from 1st amp? Thanks again!
 

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The only way it is possible but you need to be sure both inputs and outputs to and from the amps are identical in power and signal.
 

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Also note that doubling power doesn’t get tou anywhere near double the output. Doubling power will only yield 3 dB more output.
 

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this is posible. is it were 2 mono amps capable of 2 ohms or if the amps could be bridged to 2 ohms, then you could just literally wire 1 amp to each coil and double the power. but since these only bridge to 4 ohms, you will just cook the amps.

your best bet is to buy a simple 500-1000 watt mono amp and use those amps for your mids and tweets
 
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You won't ruin anything, but yea. You could do that. Thing is matching both Amps is not easy.

SMD has a Tool that match the amps output. This is something you can do at a shop that has the equipment. You can't really do it by ear but you can get close with test tones... But its really not recommended.

I get the excitement, and really, you will come into more money in time. So experiment. Since both amps are the same, you can eye the level controls, but trust me on this. They are never the same. Close but not same. And they to tend to drift out of spec over time.


It won't hurt anything to try it out. See how you like it. I was a Beginner Noob too. Still am in many respects. I still can't handle proper speaker design and how to really design a proper 2 way speaker like some of the guys Like Nelson Pass or others. But nothing stops you from getting there. It just takes time and being into doing it.

The reason why you should be cautious is simply how the the Amplifier works. See, you know have 4 amp channels that are actually being summed to 1. But to the Amplifier? Internally you asking how many ever rails it uses to get its Output Mosfets to work together. So imagine all of us on this thread singing Happy Birthday. There is always that dude that has to sing it all out of key.

Well, that causes amplifier stability or linearity issues. (Very Basically speaking) and the push pull configuration can cause the amps to become unstable. This can lead to blown mosfets in the output stage. Arguably, if everything is balanced, then its fine. In fact, one amp could then back flow current to the other causing issues.

This depends a lot more on the topology of the amp. And that's why the idea of learning all this stuff asap is sort of .. Well. Kind of hard to understand. There is just a LOT to go over. And I know its hard to believe, but most of this stuff is self taught. There are no real classes in Audio that I know off. Sure there are now Installer schools but that's just like going to a boot camp.

To reference, A guy like Nelson Pass, Bob Carver, and that dude that worked for Infinity for a while could fill up a SMALL library top to bottom with books if you took what they knew in their brains and put it on paper. Those guys are damn right engineers. But if you wanted to ask anyone about Horn design? That would be another guy over at JBL. And then the list goes on and on.

If your amps are under warranty? Sure give it a shot. If you can afford to replace them? Again, try it.

But just like that dude that found a Grenade and ran over it.. We never heard from Anon ever again after he told us he was going to shoot it with a bullet. We may never hear from you again, and you MAY kill your amps and then start a channel like barevids where you fix them.

Again. GO for it. The worst that could happen is that you learn something.

If you want to see if this works for cheap? Order some Ebay amps for like 4 bucks and try that out on your old stock speakers and see if it works. Make sure to check out the coil temps if you can. You will notice twice the bias current in the coil being possible. Its not much but its something to take note.

Rember, Push pull amps use the Back EMF of the driver. This should not cause to many problems. But some amplifier topologies really don't like being run like this. You may have an AMP go or cycle into protect.


Also note that doubling power doesn’t get tou anywhere near double the output. Doubling power will only yield 3 dB more output.

Yup.

You would be far better off making a box then doubling power. That's not quite as simple or cheap today as just adding more power. Remember back in the WAY WAY BACK... Jenson use to use 20 Watts RMS to fill a theatre with sound. and some INSANE SPL from a single woofer. The enclosure was large, and it worked great. But there is no free lunch out there. The best thing about the car is the Gain you get in the car. And that can have its own problems.


I'm kind of surprised Big D Wiz in his $150 SPL challenge did not build a Horn loaded subwoofer box. You should think about that. Do you have some Spare 6x9 drivers laying around? Or maybe some free speakers on Craigslist?

Get some foam board at Lowes, Home depot so its easy to work with and test some enclosure designs first. Its easy to work with and if done right, will give you a pretty good idea of what box design is going to give you the most output per watt of power.

Read up on Subwoofer designs for low power and High output some people used in the 80's and 90's before power got cheap.

But please read into 6th order Bandpass and Horn loading. There is subwoofer called the Bass tuba that works pretty well for output.

You know minus Vance, all the really good books on audio are all kind of hidden away. But almost ALL OF IT IS FREE.
Just go to any local Library, and you will be able to check out some of this stuff. From loudspeaker design, to much more.

A really good primer is to read up on stuff from Jenson in the 1950's and how they were able to make 3-10 watts sound like 100 today. It was ALL in the driver and the box. But it was more like they were making Musical instruments then speakers.

There as far as I know not much here about people making their own amps, so go look up info on that. That will tell you more about how and why some amps like to be bridged and some do not etc.

Before you know it, you may be making a new box to show us that hits massively hard and loud. Even with just a basic 100 amp with maybe 1000W peak output using 4 Basic budget woofers.

You never know! Good luck brother.
 

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You won't ruin anything, but yea. You could do that. Thing is matching both Amps is not easy.

SMD has a Tool that match the amps output. This is something you can do at a shop that has the equipment. You can't really do it by ear but you can get close with test tones... But its really not recommended.

I get the excitement, and really, you will come into more money in time. So experiment. Since both amps are the same, you can eye the level controls, but trust me on this. They are never the same. Close but not same. And they to tend to drift out of spec over time.


It won't hurt anything to try it out. See how you like it. I was a Beginner Noob too. Still am in many respects. I still can't handle proper speaker design and how to really design a proper 2 way speaker like some of the guys Like Nelson Pass or others. But nothing stops you from getting there. It just takes time and being into doing it.

The reason why you should be cautious is simply how the the Amplifier works. See, you know have 4 amp channels that are actually being summed to 1. But to the Amplifier? Internally you asking how many ever rails it uses to get its Output Mosfets to work together. So imagine all of us on this thread singing Happy Birthday. There is always that dude that has to sing it all out of key.

Well, that causes amplifier stability or linearity issues. (Very Basically speaking) and the push pull configuration can cause the amps to become unstable. This can lead to blown mosfets in the output stage. Arguably, if everything is balanced, then its fine. In fact, one amp could then back flow current to the other causing issues.

This depends a lot more on the topology of the amp. And that's why the idea of learning all this stuff asap is sort of .. Well. Kind of hard to understand. There is just a LOT to go over. And I know its hard to believe, but most of this stuff is self taught. There are no real classes in Audio that I know off. Sure there are now Installer schools but that's just like going to a boot camp.

To reference, A guy like Nelson Pass, Bob Carver, and that dude that worked for Infinity for a while could fill up a SMALL library top to bottom with books if you took what they knew in their brains and put it on paper. Those guys are damn right engineers. But if you wanted to ask anyone about Horn design? That would be another guy over at JBL. And then the list goes on and on.

If your amps are under warranty? Sure give it a shot. If you can afford to replace them? Again, try it.

But just like that dude that found a Grenade and ran over it.. We never heard from Anon ever again after he told us he was going to shoot it with a bullet. We may never hear from you again, and you MAY kill your amps and then start a channel like barevids where you fix them.

Again. GO for it. The worst that could happen is that you learn something.

If you want to see if this works for cheap? Order some Ebay amps for like 4 bucks and try that out on your old stock speakers and see if it works. Make sure to check out the coil temps if you can. You will notice twice the bias current in the coil being possible. Its not much but its something to take note.

Rember, Push pull amps use the Back EMF of the driver. This should not cause to many problems. But some amplifier topologies really don't like being run like this. You may have an AMP go or cycle into protect.





Yup.

You would be far better off making a box then doubling power. That's not quite as simple or cheap today as just adding more power. Remember back in the WAY WAY BACK... Jenson use to use 20 Watts RMS to fill a theatre with sound. and some INSANE SPL from a single woofer. The enclosure was large, and it worked great. But there is no free lunch out there. The best thing about the car is the Gain you get in the car. And that can have its own problems.


I'm kind of surprised Big D Wiz in his $150 SPL challenge did not build a Horn loaded subwoofer box. You should think about that. Do you have some Spare 6x9 drivers laying around? Or maybe some free speakers on Craigslist?

Get some foam board at Lowes, Home depot so its easy to work with and test some enclosure designs first. Its easy to work with and if done right, will give you a pretty good idea of what box design is going to give you the most output per watt of power.

Read up on Subwoofer designs for low power and High output some people used in the 80's and 90's before power got cheap.

But please read into 6th order Bandpass and Horn loading. There is subwoofer called the Bass tuba that works pretty well for output.

You know minus Vance, all the really good books on audio are all kind of hidden away. But almost ALL OF IT IS FREE.
Just go to any local Library, and you will be able to check out some of this stuff. From loudspeaker design, to much more.

A really good primer is to read up on stuff from Jenson in the 1950's and how they were able to make 3-10 watts sound like 100 today. It was ALL in the driver and the box. But it was more like they were making Musical instruments then speakers.

There as far as I know not much here about people making their own amps, so go look up info on that. That will tell you more about how and why some amps like to be bridged and some do not etc.

Before you know it, you may be making a new box to show us that hits massively hard and loud. Even with just a basic 100 amp with maybe 1000W peak output using 4 Basic budget woofers.

You never know! Good luck brother.
All that writing for the very wrong answer??

He has a pair of stereo amplifiers that you can’t bridge, and are stable into 4 ohms, so there is no way he can use two on one dual 2 ohm subwoofer, nor can he bridge them together which is what he’s asking

to the OP buy a mono amplifier that’s one ohm stable and run that on the dual two ohm subwoofer :)
 

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Discussion Starter #10
this is posible. is it were 2 mono amps capable of 2 ohms or if the amps could be bridged to 2 ohms, then you could just literally wire 1 amp to each coil and double the power. but since these only bridge to 4 ohms, you will just cook the amps.

your best bet is to buy a simple 500-1000 watt mono amp and use those amps for your mids and tweets
Ok thanks for all the help and advice.
 

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I really appreciate your time and effort to help me get some knowledge of audio and will take the box building seriously. I do know acoustic environment is very important to getting the most from a driver with good sound. Thanks again!
 

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No problem dude. I was there once too. Heck I have a photo someplace where I had 8 12 inch woofers and ran 4 different amps. It was HORRIBLE! Sure it looked cool, but I had almost as much output from 2 Subwoofers put in the right boxes then just thrown in Ready built boxes I got from Best buy. Souned like crap.



He has a pair of stereo amplifiers that you can’t bridge, and are stable into 4 ohms, so there is no way he can use two on one dual 2 ohm subwoofer, nor can he bridge them together which is what he’s asking

It can't be bridged? :) (I know... I just can't help it!)
So... I guess we better let Dual know that this is wrong in the middle. LOL...





Proof that it can be bridged. LOL.. Yea,,, I know.....


I'm just going off from Kickers Data sheet, but ... In a box? With Box rise? The real load to the amp is going to be 3.5 Ohms active nominal per coil. Not a static 2 Ohm resistive load.

OP asked if he could use 2 Amps, both in Bridged mode to drive each coil from what I understood his question being.

The Dual amp can do this at 4 ohms bridged as per speaker coil, is only 3.7 in use and higher with Box rise.

You can use 2 identical amps to drive each side of the voice coil as I have done it in a Walmart parking lot with a DVC subwoofer with these very amps. So it can be done in a pinch.

Should you? No. But you can.


You won't get much more out of it. The Voice coils my run much hotter, but you will get a bit more output. Again, as a test to see if it works, fine.

But I would never run it that way. TO much hassle. But I did it in a pinch. Granted, I had test gear used for Telecoms at my disposal. And it was either this, or 400 mile drive with no Subwoofer. Both amps were given to a work buddy, and still work today.

Again, its possible. But not recommend.
 

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the short answer is you can't. The longer answer is these 2 amps do not match up with a D2 sub. As stated above get a mono amp able to run 1 ohm or 4ohm and put out 750-1000 watts at whichever configuration you choose.
 

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Yeah, can't do it. If you don't see a master + slave switch on both amps and wiring instructions in the manual on how to combine 2 exact/same amps into a big monster... please don't do it.
Plus the amp itself is not stable at 2ohm bridged, and it would need to be since he has a D2 sub.
 

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So let me get this straight...
You have 6 people saying that this can't (or definitely shouldn't) be done... and one guy who says that it is totally fine.
Then you respond to the one guy that told you it was OK?

If I'm reading between the lines, my guess is that; you are fully intent on hooking both of these amps up to one sub.
You don't wan't advice. What you're actually looking for; is someone to validate your bad idea.

I say DO IT!
 

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No problem dude. I was there once too. Heck I have a photo someplace where I had 8 12 inch woofers and ran 4 different amps. It was HORRIBLE! Sure it looked cool, but I had almost as much output from 2 Subwoofers put in the right boxes then just thrown in Ready built boxes I got from Best buy. Souned like crap.






It can't be bridged? :) (I know... I just can't help it!)
So... I guess we better let Dual know that this is wrong in the middle. LOL...





Proof that it can be bridged. LOL.. Yea,,, I know.....


I'm just going off from Kickers Data sheet, but ... In a box? With Box rise? The real load to the amp is going to be 3.5 Ohms active nominal per coil. Not a static 2 Ohm resistive load.

OP asked if he could use 2 Amps, both in Bridged mode to drive each coil from what I understood his question being.

The Dual amp can do this at 4 ohms bridged as per speaker coil, is only 3.7 in use and higher with Box rise.

You can use 2 identical amps to drive each side of the voice coil as I have done it in a Walmart parking lot with a DVC subwoofer with these very amps. So it can be done in a pinch.

Should you? No. But you can.


You won't get much more out of it. The Voice coils my run much hotter, but you will get a bit more output. Again, as a test to see if it works, fine.

But I would never run it that way. TO much hassle. But I did it in a pinch. Granted, I had test gear used for Telecoms at my disposal. And it was either this, or 400 mile drive with no Subwoofer. Both amps were given to a work buddy, and still work today.

Again, its possible. But not recommend.
It CAN be bridged...to 4ohm load. NOT to a 2ohm load. So tell me how you take a pair of 4ohm stable bridged amps, and power a D2 sub? I'll wait. :)
 
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No problem dude. I was there once too. Heck I have a photo someplace where I had 8 12 inch woofers and ran 4 different amps. It was HORRIBLE! Sure it looked cool, but I had almost as much output from 2 Subwoofers put in the right boxes then just thrown in Ready built boxes I got from Best buy. Souned like crap.






It can't be bridged? :) (I know... I just can't help it!)
So... I guess we better let Dual know that this is wrong in the middle. LOL...





Proof that it can be bridged. LOL.. Yea,,, I know.....


I'm just going off from Kickers Data sheet, but ... In a box? With Box rise? The real load to the amp is going to be 3.5 Ohms active nominal per coil. Not a static 2 Ohm resistive load.

OP asked if he could use 2 Amps, both in Bridged mode to drive each coil from what I understood his question being.

The Dual amp can do this at 4 ohms bridged as per speaker coil, is only 3.7 in use and higher with Box rise.

You can use 2 identical amps to drive each side of the voice coil as I have done it in a Walmart parking lot with a DVC subwoofer with these very amps. So it can be done in a pinch.

Should you? No. But you can.


You won't get much more out of it. The Voice coils my run much hotter, but you will get a bit more output. Again, as a test to see if it works, fine.

But I would never run it that way. TO much hassle. But I did it in a pinch. Granted, I had test gear used for Telecoms at my disposal. And it was either this, or 400 mile drive with no Subwoofer. Both amps were given to a work buddy, and still work today.

Again, its possible. But not recommend.
He wants to bridge two stereo amplifiers together (four channels to one load!)... not two channels of one amplifier! So I’ll accept your apologies in your next non factual post!
 

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He wants to bridge two stereo amplifiers together (four channels to one load!)... not two channels of one amplifier! So I’ll accept your apologies in your next non factual post!




Okay lets do this. I don't have Op's subwoofer, but I do have the 2 ohm per voice coil MOFO15 still in my living room. I did this Very thing on my subwoofer just as I said with the very same amps I purchased from walmart.

So subscribe to this thread, and I will pick up 2 of these amps and do the same test and video tape it for you that it indeed worked for the trip till I could get my hands on a propper amp. Deal?

That way we can lay this one to rest. Again, it worked for me hooking it up. Not doing anything fancy. Granted I was not blasting the thing, but it worked well enough for me to try it out and nothing exploded.

On paper it seems like it would not work. But then again, how many Home receivers are only rated at 8 ohms and will drive a 4 ohm car speaker. Same thing here.

Let me see what amps I have Kicking around and see if I can get sme bridged that only work at 4 ohms, and get two of them. I think I have an old 4 channel Sony, and a 4 channel. Blaupunkt I think both of those are only rated to drive a 4 ohm load bridged per 2 channels on each side. I can do that this next week.

Or I can wait till some Stingy Company pays me so I can pick up the amps. Should be around the first. Love being a contractor.


I will load up the video in a bit after the first. That reminds me, I need to build a 14.4v power supply. So it gets that out of the way. I got 2 AGM's just sitting around, so I can use those as well as they are identical.

Source unit will be an phone and some RCA's for the test.

Anything else you guys recommend for the testing?
 
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