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No, only if you add a line level converter before the amp. Sorry, my post was confusing... There are inexpensive ones like the Kicker or premium like the LC2i...



I'm not saying the line level converter is needed, just said that it's something I would consider at this point. Lots out there running the high level inputs in stereo and it's working great.
I see now. Yea I was thinking about adding the line level converters. I'm not sure yet. I have the gain up about 25% on the amp. I'm willing to bet that's pushing it to produce 80%-90% of its RMS power since its a line level input. I think what I did hit the sweet spot.
 

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1. Which amp did you go with? I'm thinking of using the Alpine MRV-M500 referenced earlier in this thread.
2. How did you mount the amp? I'm assuming screwed through the floor pan and then just put some silicon caulk on the underside where screws protrude?
I went with the Alpine MRV-M500, along with the dynamat and Pioneer sub. However I have the aftermarket Alpine restyle head unit so I was able to get line-level inputs to the amp. Whether you use line level or a step down from speaker level, the amp has plenty of power to drive the pioneer sub. You can “feel” the difference. I also added the Alpine amp remote control knob to allow easy adjustment of gain based on what music is being played.

Like others I also mounted under the passenger seat. I fashioned a bracket using small L-shaped metal shelving brackets I bought from Home Depot and mounted those to the seat rail (had to remove the seat first), then the amp to the brackets. It’s a solid install and a HUGE boost in sound quality.
 

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@Redstapler IMO you are taking a chance with you sub and your amp. First the beauty of DVC speaker is that you have option of what impedance you can run, not that it can handle stereo inputs. Unless the amp is putting out the same power on each channel, unlikely, it can rip up the sub. If the music has multiple bass focal points the bass sound will be muddy, instead of 2 distinct bass note you get one. If the voice coils are not moving in the same direction and the same amplitude at all times you will have an issues down the road.

Your sub out should be in the bridged mode with the low pass filter set to on. In general for a 8 inch speaker you want 125hz as the cutoff. Wire the speaker in series, amp to speaker voice coil one + to +, voice coil one to voice coil 2, - to +, and voice coil 2 to amp, - to -. Your amp will see 4 ohms in this configuration. A single 2 ohm DVC speaker can be configured either 1 or 4 ohms.

At least this is what I would do. I have all the equipment to measure power, set cross overs and detect distortion before you can hear it. I have a pretty high end amp and when I measured the difference between the A and the B channels it was like a 15 watt difference, or to put it another way over 10%.
 

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I see now. Yea I was thinking about adding the line level converters. I'm not sure yet. I have the gain up about 25% on the amp. I'm willing to bet that's pushing it to produce 80%-90% of its RMS power since its a line level input. I think what I did hit the sweet spot.

Yep, you got it. Many of the PRS+ builders have tried to use the amp bridged in mono, they just don't work as well. I think everyone has converted to wired in stereo with the best results. So much more control in the bass.

I also say that it isn't the way we would normally do it... Normally you would want the amp bridged and the sub wired to 4 ohms as Terry posted above. It just doesn't work in this application.
 

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@Redstapler IMO you are taking a chance with you sub and your amp. First the beauty of DVC speaker is that you have option of what impedance you can run, not that it can handle stereo inputs. Unless the amp is putting out the same power on each channel, unlikely, it can rip up the sub. If the music has multiple bass focal points the bass sound will be muddy, instead of 2 distinct bass note you get one. If the voice coils are not moving in the same direction and the same amplitude at all times you will have an issues down the road.

Your sub out should be in the bridged mode with the low pass filter set to on. In general for a 8 inch speaker you want 125hz as the cutoff. Wire the speaker in series, amp to speaker voice coil one + to +, voice coil one to voice coil 2, - to +, and voice coil 2 to amp, - to -. Your amp will see 4 ohms in this configuration. A single 2 ohm DVC speaker can be configured either 1 or 4 ohms.

At least this is what I would do. I have all the equipment to measure power, set cross overs and detect distortion before you can hear it. I have a pretty high end amp and when I measured the difference between the A and the B channels it was like a 15 watt difference, or to put it another way over 10%.
That's a thought I had considered before. I know that certain song are edited for left to right differentiation on stereo sound and as such the bass would shift sides and result in this case causing a delta in the power being fed to each coil.

The logic I employed is unique to this amp. Idk if you have seen the alpine amp that comes from the factory apline system but each speaker has its own channel. This includes the front tweeter and woofer having a dedicating line straight from the amp as opposed to one line that branches to a crossover.

Even stranger is the sub wires. From the amp it comes out as two sets of (+) (-) wires that both run to one of the coils on the sub. My assumption is that if the factory sub was receiving this type of dedicated line to each coil, the system must be set up to send the same level to each coil.

I really don't know for sure if this is the case. It's just a best guess based on the strange factory system. I'm going to see where it goes. If I was wiring this to an aftermarket system I would have went a different route.

Feel free to let me know if I'm completely wrong. I won't get offended! Haha
 

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1. I used a Dual XPR82D. Its pretty cheap and can be bought at most advance auto parts stores. My goal with this was to be cheap but not too cheap. The Alpine amp you mentioned is a good amp. Keep in mind though its a mono amp so you wouldn't be able to wire it like I did on mine.

Also if you go with the Alpine, you're gonna need to get a line level converted for the inputs. With that power its gonna be strong even with the gain at 0.

2. I actually used velcro strips that I had. Idk where I got them but they're a special kind that can bond to carpet, metals, plastic etc.

I hope the dynamat seals you up! Making the seal made the difference between good and great sound for me. Good luck!
@Redstapler IMO you are taking a chance with you sub and your amp. First the beauty of DVC speaker is that you have option of what impedance you can run, not that it can handle stereo inputs. Unless the amp is putting out the same power on each channel, unlikely, it can rip up the sub. If the music has multiple bass focal points the bass sound will be muddy, instead of 2 distinct bass note you get one. If the voice coils are not moving in the same direction and the same amplitude at all times you will have an issues down the road.

Your sub out should be in the bridged mode with the low pass filter set to on. In general for a 8 inch speaker you want 125hz as the cutoff. Wire the speaker in series, amp to speaker voice coil one + to +, voice coil one to voice coil 2, - to +, and voice coil 2 to amp, - to -. Your amp will see 4 ohms in this configuration. A single 2 ohm DVC speaker can be configured either 1 or 4 ohms.

At least this is what I would do. I have all the equipment to measure power, set cross overs and detect distortion before you can hear it. I have a pretty high end amp and when I measured the difference between the A and the B channels it was like a 15 watt difference, or to put it another way over 10%.
That's a thought I had considered before. I know that certain song are edited for left to right differentiation on stereo sound and as such the bass would shift sides and result in this case causing a delta in the power being fed to each coil.

The logic I employed is unique to this amp. Idk if you have seen the alpine amp that comes from the factory apline system but each speaker has its own channel. This includes the front tweeter and woofer having a dedicating line straight from the amp as opposed to one line that branches to a crossover.

Even stranger is the sub wires. From the amp it comes out as two sets of (+) (-) wires that both run to one of the coils on the sub. My assumption is that if the factory sub was receiving this type of dedicated line to each coil, the system must be set up to send the same level to each coil.

I really don't know for sure if this is the case. It's just a best guess based on the strange factory system. I'm going to see where it goes. If I was wiring this to an aftermarket system I would have went a different route.

Feel free to let me know if I'm completely wrong. I won't get offended! Haha
OK, a follow-up question from the novice due to these posts. I have the Pioneer DVC replacement subwoofer described in this thread. What are the pros/cons of wiring in stereo vs. bridging?
 

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Yep, you got it. Many of the PRS+ builders have tried to use the amp bridged in mono, they just don't work as well. I think everyone has converted to wired in stereo with the best results. So much more control in the bass.

I also say that it isn't the way we would normally do it... Normally you would want the amp bridged and the sub wired to 4 ohms as Terry posted above. It just doesn't work in this application.
The custom amp from alpine definitely presents some unip
OK, a follow-up question from the novice due to these posts. I have the Pioneer DVC replacement subwoofer described in this thread. What are the pros/cons of wiring in stereo vs. bridging?
In most applications bridging yields best results bc it combines two channels into one cohesive channel that typically doubles the power. Typically bridged amps can only do a 4 ohm load when bridged. You can check it in the specs. But if you bridge an amp and it runs four ohms you will need to wire the amp in series. If you need more on how that works just ask.

Like Pressurized said and I've seen this personally: running in stereo seems to be yielding better results in this setup. Especially if you're not using a line converter to convert the speaker level inputs into line level inputs. Running stereo with speaker level has allowed me to get a better power match and sounds better overall.

Now TerryC6 told me he thinks that wiring it in stereo could have the potential to be troublesome. He would be completely right if this system wasn't as unique as it is. You can read my reply to him for details on why I think that. Now I may be completely wrong on that. I've worked with stereos quite a bit before but I'm no expert.

The best I can say is that alot of people on here report better results from a stereo setup. If it is gonna be bad like TerryC6 says, I guess I'll find out..
 

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<snip>

The best I can say is that alot of people on here report better results from a stereo setup. If it is gonna be bad like TerryC6 says, I guess I'll find out..
There are a bunch of install out there in stereo for a few years now and no issues that I am aware of.

If we were to use the line level converter, we could the send the low level signal in stereo to the amp and bridge and low pass with the amp... I think that's how we have to build if we want to bridge. The factory amp isn't all that powerful, so we aren't chasing a bunch of bass to keep up with the mids and highs. I am still just PRS, but I have heard a couple PRS+ and for the $$ they sound great.
 

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I really don't care if there is a bunch of people who have done it is wrong and not recommended. While it is certainly possible to do so it requires that both output signals are identical which is never the case with a stereo output. And even if you input the same it is unlikely that you would get identical left and right signals out unless you want to spend a few thousand on matched amplifiers (aftermarket).

@Redstapler first off there is nothing unique about your set up. Every amp I have ever seen has a separate amp for each channel. The stock system is a 6 channel amp but the 2 outputs to the sub is mono, not stereo. I also imagine that the amps are pretty closely matched, they are sell 10 of thousands of these systems and the amp is probably used in more than one vehicle.

You said that when you hooked it up bridged it was to loud, guess what that, is what it is suppose to sound like and has nothing to do with you using speaker level inputs, i'll get back to that. When you where running in bridge mod both voice coils are working together, when you are in stereo they are fighting each other.

If I remember correctly the stock amp is 36 watts a channel, that is only about 8.5 volts at 2 ohm, 12 volts at 4 ohms. The amp will take these inputs and step them down to a voltage that the amp can use, nothing magical about that. You set the gain for the output, which for your amp is going to be about 21 volts.

One other data point to drive it home, when you are running it as stereo the output is 120 watts or 21 volts at 2 ohms. When you are running bridged its is 240 watts or 21 volts at 4 ohms. It can not run bridged at 2 ohms. With all being the same one will not be louder than the other. Again this is a sign the voice coils are fighting.

And last but not least, look at you owners manual. Do you see one case where they recommend running a sub in stereo? Nope in every case it is bridged.


FYI: One amp per speaker is called an active set up. This can only be accomplished properly with the using one of more DSP's depending on the number of speakers being run. These are the kinds of setup you would see in competition level SQ setups. I may move this direction in the future as many of the newer DSP allow for Bluetooth inputs and this would be perfect for a tablet solution. I really don't need radio any more.

Sorry for the long post.
 

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I really don't care if there is a bunch of people who have done it is wrong and not recommended. While it is certainly possible to do so it requires that both output signals are identical which is never the case with a stereo output. And even if you input the same it is unlikely that you would get identical left and right signals out unless you want to spend a few thousand on matched amplifiers (aftermarket).

@Redstapler first off there is nothing unique about your set up. Every amp I have ever seen has a separate amp for each channel. The stock system is a 6 channel amp but the 2 outputs to the sub is mono, not stereo. I also imagine that the amps are pretty closely matched, they are sell 10 of thousands of these systems and the amp is probably used in more than one vehicle.

You said that when you hooked it up bridged it was to loud, guess what that, is what it is suppose to sound like and has nothing to do with you using speaker level inputs, i'll get back to that. When you where running in bridge mod both voice coils are working together, when you are in stereo they are fighting each other.

If I remember correctly the stock amp is 36 watts a channel, that is only about 8.5 volts at 2 ohm, 12 volts at 4 ohms. The amp will take these inputs and step them down to a voltage that the amp can use, nothing magical about that. You set the gain for the output, which for your amp is going to be about 21 volts.

One other data point to drive it home, when you are running it as stereo the output is 120 watts or 21 volts at 2 ohms. When you are running bridged its is 240 watts or 21 volts at 4 ohms. It can not run bridged at 2 ohms. With all being the same one will not be louder than the other. Again this is a sign the voice coils are fighting.

And last but not least, look at you owners manual. Do you see one case where they recommend running a sub in stereo? Nope in every case it is bridged.


FYI: One amp per speaker is called an active set up. This can only be accomplished properly with the using one of more DSP's depending on the number of speakers being run. These are the kinds of setup you would see in competition level SQ setups. I may move this direction in the future as many of the newer DSP allow for Bluetooth inputs and this would be perfect for a tablet solution. I really don't need radio any more.

Sorry for the long post.
With all due respect, have you done exactly what we are doing? We all tried it the normal way. I used to build competition systems years ago, was sponsored by Concord and Linear Power. I know how it's "normally" done. In this specific application, stereo gives better results. Plain and simple. Without adding any additional components, etc it sounds better, tonal quality is better and it's cleaner and clearer and plays just as loud. Please don't ignore where we are saying "THIS SPECIFIC APPLICATION ONLY". If 30 people do something both ways and the result is 30 people get better results doing it one way versus another, what's the conclusion? It still wrong? See what we are saying?

Cheers.
 

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With all due respect, have you done exactly what we are doing? We all tried it the normal way. I used to build competition systems years ago, was sponsored by Concord and Linear Power. I know how it's "normally" done. In this specific application, stereo gives better results. Plain and simple. Without adding any additional components, etc it sounds better, tonal quality is better and it's cleaner and clearer and plays just as loud. Please don't ignore where we are saying "THIS SPECIFIC APPLICATION ONLY". If 30 people do something both ways and the result is 30 people get better results doing it one way versus another, what's the conclusion? It still wrong? See what we are saying?

Cheers.
I don't get this. Are you saying you're splitting a MONO signal and sending that same signal to a multiple coil sub through different amps, or are you saying you're feeding a STEREO signal (left and right) to a multiple coil sub through different amps?


A stereo signal is not advisable and can destroy your sub with unique pieces of music. Most of the time the low end signals (drum beats... etc) between left and right is common so there isn't an issue, but if you get a unique piece where the low end signals are not common then then the signals compete with each other for dominance which results in signals cancelled generating unnecessary heat on the coils and a muddy signal as the cone is trying to react to both signals at the same time.

A split mono signal on the other hand can sound clearer and more precise from different amps... so long as those amps are pretty closely matched. The cone effectively gets twice the power at the same moment in time causing it to react faster and more aggressively... bigger, clearer bang... but the amps have to be of pretty good quality because if they don't deliver that same signal at that same moment in time at the same gain, then instead of the signals being additive to each other, you get into the stereo effect above where signals are being cancelled.... yadda yadda
 

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With all due respect, have you done exactly what we are doing? We all tried it the normal way. I used to build competition systems years ago, was sponsored by Concord and Linear Power. I know how it's "normally" done. In this specific application, stereo gives better results. Plain and simple. Without adding any additional components, etc it sounds better, tonal quality is better and it's cleaner and clearer and plays just as loud. Please don't ignore where we are saying "THIS SPECIFIC APPLICATION ONLY". If 30 people do something both ways and the result is 30 people get better results doing it one way versus another, what's the conclusion? It still wrong? See what we are saying?

Cheers.
Electronics and the way a speaker operates does not change based on vehicle application. What do you think is happening when the right channel is demanding 14v and the left only 3v? For a DVC sub to work correctly inputs have to be the same. And this is the exact reason Redstapler got louder results when he bridged the system.
 

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I don't get this. Are you saying you're splitting a MONO signal and sending that same signal to a multiple coil sub through different amps, or are you saying you're feeding a STEREO signal (left and right) to a multiple coil sub through different amps?
Remember that a 2 channel amp is actually 2 amps. But what they are doing amp or not is applying the left channel to one coil and the right channel to the other coil.
 

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I don't get this. Are you saying you're splitting a MONO signal and sending that same signal to a multiple coil sub through different amps, or are you saying you're feeding a STEREO signal (left and right) to a multiple coil sub through different amps?


A stereo signal is not advisable and can destroy your sub with unique pieces of music. Most of the time the low end signals (drum beats... etc) between left and right is common so there isn't an issue, but if you get a unique piece where the low end signals are not common then then the signals compete with each other for dominance which results in signals cancelled generating unnecessary heat on the coils and a muddy signal as the cone is trying to react to both signals at the same time.

A split mono signal on the other hand can sound clearer and more precise from different amps... so long as those amps are pretty closely matched. The cone effectively gets twice the power at the same moment in time causing it to react faster and more aggressively... bigger, clearer bang... but the amps have to be of pretty good quality because if they don't deliver that same signal at that same moment in time at the same gain, then you get into the stereo effect above where signals are being cancelled.... yadda yadda
Signal is from the same amp 2 channels... We don't know if the factory amp is a mono signal through 2 channels. But all we're doing is mimicking the factory set up with another amp in the signal.

Electronics and the way a speaker operates does not change based on vehicle application. What do you think is happening when the right channel is demanding 14v and the left only 3v? For a DVC sub to work correctly inputs have to be the same. And this is the exact reason Redstapler got louder results when he bridged the system.
But you didn't answer my question... Have you done it? Obviously the answer is no. And I couldn't care less what you think is happening.... For all we know, the factory amp is putting out the same signal to both channels. Like a mono signal run in stereo... By the way, it was louder only at the same input level settings. It doesn't play any louder at clipping levels...

I'll leave it with this... Why did both Infinity and Alpine design the system this way? The sub is a DVC run off of 2 separate amp channels from the factory... I assume you know more than they do?

I'm out.
 

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Remember that a 2 channel amp is actually 2 amps. But what they are doing amp or not is applying the left channel to one coil and the right channel to the other coil.
Yeah... not advisable.
As noted above in most cases there won't be an issue and it may actually sound pretty good because modern music mixing usually places low end signals equally between left and right channels... but all you need is one piece with unique music mixing qualities....

If you want to run a multiple coil sub with multiple amps than its best to use a mono signal split between the two amps. That way you can assure both amps will ALWAYS get the exact same signal.
 

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I'll leave it with this... Why did both Infinity and Alpine design the system this way?
The signals are matched. Match the signals and I agree, it sounds good... and that's why they do it.

A STEREO signal isn't always necessarily matched though.. and that is where you get into trouble.

What is
+6 volts left channel + 6 volts right channel?
Easy... 12 volts
If you are feeding +6 volts to the two coils at the same moment in time then the signal is additive and your cone will move to the addition of those voltages.

Let's place the channels out of phase. We'll do an extreme out of phase just for the example... 180 degrees... completely opposite.
What is
(+6 volts) + (-6 volts)
Again... two signals to the coil at the same time is additive and the result this time is ZERO. The +6v trying to push the cone up is exactly canceled by the -6v trying to push the cone down... all at the same time.
Given that, your cone (technically) will not react at all and produce little more than heat. (In reality you may hear a bit of sound since you can never get two signals producing at the EXACT same time)

But anyway.... all this kind of gives one an idea of how good things can be if the signals are an exact match.... and what can happen if they are not.
At the end of the day a stereo signal can work... but it's not safe.
Safer to use a mono signal which is split to the two amps

If you wish to combine your left and right channels for fear of missing something then get a mixer box which will mix left/right to a mono signal, then split that signal to your amps. Indeed that's basically what a traditional sub output is on the back of any home or automotive receiver... a mixed left/right output to mono... and that is also in essence what infinity/alpine are doing.
 

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  1. Signal is from the same amp 2 channels... We don't know if the factory amp is a mono signal through 2 channels. But all we're doing is mimicking the factory set up with another amp in the signal.



    But you didn't answer my question... Have you done it? Obviously the answer is no. And I couldn't care less what you think is happening.... For all we know, the factory amp is putting out the same signal to both channels. Like a mono signal run in stereo... By the way, it was louder only at the same input level settings. It doesn't play any louder at clipping levels...

    I'll leave it with this... Why did both Infinity and Alpine design the system this way? The sub is a DVC run off of 2 separate amp channels from the factory... I assume you know more than they do?

    I'm out.
    The original idea here was to make the factory system better with minimal work. I don't pretend to know everything about the stock amp in this system but like you said in my setup I'm running the exact same setup as the original. I'm just adding the amp in line. Its powering the same signal that the original sub was receiving in the same way.... If the issue of "unique" sound would be an issue with the original system it would be an issue just as much with the upgraded scenario that I now have. At the end of the day this project was about better sound for cheap. I'm being a cheapo here. So if I end up hurting my $70 sub in 3 years bc I listened to a "unique" song, so be it haha. I really don't care. If I was going to spend the money for what these guys were saying to do earlier I might as well have replaced the whole stereo
 

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One last question for the experts. I was poking around and looking at my options for amps. I can either go with the Dual Electronics amp Redstapler used or a JBL I found at Crutchfield:
Dual - https://www.walmart.com/ip/Dual-Electronics-XPR82D-2-1-High-Performance-Power-MOSFET-Class-D-Car-Amplifier-with-600-Watts-of-Dynamic-Peak-Power/520549144?athpgid=athenaItempage_137888849&athctxid&athcpid=520549144&atlmtid=BuyTogetherValue&athcgid&athena=true&athieid=v0&athbktid&athstid=CS002&athguid=a8b1aa15-22e-1721433e737130
JBL - JBL Stadium 2 2-channel car amplifier — 100 watts RMS x 2 at Crutchfield

Dual is $60, JBL is $120
Both rated at 120 watts RMS x 2 channel at 2 Ohms
Both handle speaker level inputs
JBL has 32-320 Hz crossover while Dual is 40-250 Hz
Dual has better signal to noise ratio at 100 dBA vs. JBL at 80 dBA
JBL has wider frequency response at 15-35k Hz vs. Dual at 20-20k Hz
Dual has variable base boost @50 Hz (0-12 dB)

So, the million dollar (or $60!) question - is the JBL worth the extra money?
 

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