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Discussion Starter #1
If you've got the 180watt factory system, than this is for you.
1.Fade your stereo to the rears and check if you have decent bass.
2.Fade all the way to the fronts and check for bass.
3.Fade to the center and you'll most likely realize that the bass is gone! Why is this? Well I found that the rears and the fronts were out of phase from each other. And we all know that out of phase = zero bass. So I went to my shop and picked up 2 nissan harnesses. I then pulled out the factory stereo and switched the polarity on the rear speakers (sub goes through the same wires). Well what do you know, I got the bass back. Not that it is overwhelming, but way better than before. I'm wondering if this problem is internal from the radio or from the wiring to the speakers.

Let me know if you guys/girls have had this problem with the factory stereo. And if this solution works. Any q's let me know. Thanks.

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97 nissan 240 se, stock (for now) except for custom sounds.
01 nissan sentra se/pp, stock (my girl's car).
 

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Nissan built the factory system out of phase? Geez what were they thinking. I think you can also buy a phase shifter that slightly offsets the phase on a speaker so that it plays normally but im not sure how much that is.

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Neil
Visionology Interactive
http://www.visim.com
 

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the deck runs only the fronts and the reares. the signal for the sub is taken from the rear. you will notice the wirings from the back.
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Nismo240:
If you've got the 180watt factory system, than this is for you.
1.Fade your stereo to the rears and check if you have decent bass.
2.Fade all the way to the fronts and check for bass.
3.Fade to the center and you'll most likely realize that the bass is gone! Why is this? Well I found that the rears and the fronts were out of phase from each other. And we all know that out of phase = zero bass. So I went to my shop and picked up 2 nissan harnesses. I then pulled out the factory stereo and switched the polarity on the rear speakers (sub goes through the same wires). Well what do you know, I got the bass back. Not that it is overwhelming, but way better than before. I'm wondering if this problem is internal from the radio or from the wiring to the speakers.

Let me know if you guys/girls have had this problem with the factory stereo. And if this solution works. Any q's let me know. Thanks.

<HR></BLOCKQUOTE>


hum.. couldnt you just switch them at the speaker instead of pulling the deck out?


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2001 GXE
from a i4.0 to a 1.8?
oh well
 

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Discussion Starter #5
Sure you could, but then if Mr. Nissan looks in the trunk and sees that you've hacked the factory wiring Bye Bye warranty. Besides the factory radio comes out in less than five minutes. Who has time to rewire the sub and the two rear 6's? I don't.

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97 nissan 240 se, stock (for now) except for custom sounds.
01 nissan sentra se/pp, stock (my girl's car).
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Nismo240:
If you've got the 180watt factory system, than this is for you.
1.Fade your stereo to the rears and check if you have decent bass.
2.Fade all the way to the fronts and check for bass.
3.Fade to the center and you'll most likely realize that the bass is gone! Why is this? Well I found that the rears and the fronts were out of phase from each other. And we all know that out of phase = zero bass. So I went to my shop and picked up 2 nissan harnesses. I then pulled out the factory stereo and switched the polarity on the rear speakers (sub goes through the same wires). Well what do you know, I got the bass back. Not that it is overwhelming, but way better than before. I'm wondering if this problem is internal from the radio or from the wiring to the speakers.

Let me know if you guys/girls have had this problem with the factory stereo. And if this solution works. Any q's let me know. Thanks.

<HR></BLOCKQUOTE>

What do you mean switched the polarity? How did you do this?



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2000 Sentra SE PP Black 5 spd
Just got hit and have to get a new fender!
 

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Discussion Starter #7
The speakers have a Positive + and a negative -.
When you switch the polarity, you just take the two wires and switch them.
For instance, the Positive lead goes to the - side of the speaker and the Negative lead goes to the + side of the speaker.

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97 nissan 240 se, stock (for now) except for custom sounds.
01 nissan sentra se/pp, stock (my girl's car).
 

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I just bought a 2001 SE with the 180 Watt sound system. How would I know if the speakers are out of phase or is this a problem with all systems? Also, what exactly do I need to get and do to correct the problem? i.e. What are those Nissan harnesses and where do I get them? What do I do with them when I get them? Any help would be appreciated. Thanks.
 

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One more thing. Would an aftermarket headunit solve this problem? Would it make the system sound even better? Thanks again.
 

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I agree... I have no clue what you're talkin about??

Why is it that important to do the extra work and pay the extra money? Does it make that much of a difference?

And yes, all the other questions that mj asked...
 

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That might explain the crappy sound I got on my sound system....

Well, I'll check it out, but should'nt it be done by the dealer under warrranty?
 

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Discussion Starter #12
I'm not sure on whether or not it's the factory head unit or the wiring for the speakers. So, changing the h/u might make the difference. I personally don't like the mounting kits that are currently available for the sentra. So I kept it factory

The difference was very noticeable.

I doubt that nissan is going to fix this. Remember, the stereo still works right?

I believe you need good sound in your car, it relaxes you when you drive. If sound isn't important then don't change anything. It took me all of 10 min. to do the whole thing. I don't call that work.

They sell nissan wire harnesses at your local car audio shop. Best Buy, Circuit City, etc...
 

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Nismo-What exactly do I do with the wiring harness when I get it? Will I replace the existing wiring coming out of the headunit? Thanks for the answers so far!
 

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Discussion Starter #14
1. Do you know what polarity is?
2. Have you had any experience with installing/removing car radios?

If you have answered NO to both of these questions, then your best bet would be to go to your local stereo shop and ask how much it would cost for them to switch the polarity of the rear speakers (only!) at the wire harness behind the radio. MAKE SURE THEY USE WIRE HARNESSES AND NOT SOLDER!!! Each wire harness will probably cost about $15 and you need two. If you know someone in the shop, they actually cost about $3. I would not recommend doing this procedure for the mechanically challenged. I would not like anyone to get their cars f*cked up because of a wiring error.

If you answered yes to the questions above then here ya go.
The two wire harnesses are available by Metra (metraonline.com) The numbers are: 71-7550 and the 70-7550. There are also substitutes for the Metra brand, but I wouldn't recommend it.
You will only need the small harnesses, they are for the rear speakers. Colors should be: green/black, green and purple/black and purple, there is also a blue/white. There might be a black/white, but you don't need it to connect it. Normally, you would just match the colors with the two harnesses(ie.green/black to green/black). To solve the problem, you will take the two harnesses and wire them up as follows:
Green/black to green and vise versa
Purple/black to purple and vise versa
Blue/white to blue/white (amp turn on for sub woofer)
Remember, IF YOUR CAR DOES NOT EXPERIENCE THE "OUT OF PHASE" PROBLEM, THEN DON'T REWIRE IT! JUST BECAUSE IT WORKS FOR SOME OF THE SENTRAS, IT DOESN'T MEAN IT WILL WORK FOR ALL OF THE SENTRAS.

[Edited by Nismo240 on 05-20-2001 at 09:18 PM]
 

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By the way, when you talk about the headunit, you're talking about the radio right?
And how did you took it out from the dash?

Merci!
 

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Discussion Starter #16
guy_geo said:
By the way, when you talk about the headunit, you're talking about the radio right?
And how did you took it out from the dash?

Merci!
This has been explained before many times. Use the search function.
 

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guy_geo said:
By the way, when you talk about the headunit, you're talking about the radio right?
And how did you took it out from the dash?

Merci!
The best way to get to the headunit is to start unscrewing things. That is the best way to learn. Take it apart blindly (not literally) and put it back together. Use the basic rules:
1. If it's not screwed, it's clipped.
2. If it's not clipped, the screw is hidden.
3. NEVER USE FORCE!!!
 

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Thanks a lot for the tips!
 
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