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Discussion Starter · #1 ·
after installation , I got distortion from the front right tweeter
the sound level was about 20 or a little more - with PDX-5 set to 0db

5 minutes and switched the car off when I turn it again the tweeter was gone and the woofer was very weak.

re-checked the wiring I found that the input and WF polarity were reversed.
checked the tweeter with DMM and there was no read.
and althou the woofer still have sound - very bad for sure and has about 3.5 ohm but it seems as if it's melt , it became solid.

I don't know what happened exactly. but I contacted Alpine support and the answer was:

"I have no idea how you could burn ! them so easily?? you must have put
some volume into them.... precision speakers are like engines, they must have
running in time ! 2-3 months !

You can blow them with a pdx 5, in most cases an amplifier that is too
small can blow speakers easier than one too large...
with a small amp you tend to wind up the volume more to get the output,
once distortion has been reached the power input to the speaker is much
larger as DC (direct current) will be present on the speaker signal.. so
a 20 watt amp pushed into distortion is effectively like a 60watt amp to
the speaker..."

I went and checked the PDX-5 with DMM , the DC is very low, can not cause that unless the is another reason helped in that.

can it be crossover fault? I'm afraid that I get spare parts and the same problem happen again.


The strange thing that I have 4 speakers , the left front and the rear are OK. only the right front blown.

what can cause that?

what do I have to do?
 

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Are those the multi-thousand $$ ones? :confused:
 

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It has been suggested to you previously but you have ignored the advice.

Find an an installer to connect and setup your system.

You have a lot of expensive gear, and inadequate experience to make it work and play together. You also seem unable or unwilling to learn from the product manuals, so I assume that reading the various technical threads here is of no help either.
 

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Discussion Starter · #4 ·
It has been suggested to you previously but you have ignored the advice.

Find an an installer to connect and setup your system.

You have a lot of expensive gear, and inadequate experience to make it work and play together. You also seem unable or unwilling to learn from the product manuals, so I assume that reading the various technical threads here is of no help either.
I didn't ignore your advice , I went to an installer and he is the one who reversed the polarity by mistake.

on the other hand polarity would not do that damage.
 

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Dude, how are we to troubleshoot your system from what I assume is 1000's of miles away? Go back to the installer. It is a shop warranty issue.
 

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One thing blows speakers: too much average power over time.

Dont turn it to the right quite as much.
 

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Discussion Starter · #7 ·
One thing blows speakers: too much average power over time.

Dont turn it to the right quite as much.
after testing the PDX-5 with the DMM it produce mv DC.
If I suppose that DC is the cause I wold think that there is another reason caused the amp to produce much DC.
on the other hand why Right front only , if much DC was produced most if not all speakers should be blown.

I guess the either the speakers were faulty or the crossover itself.
 

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Discussion Starter · #8 ·
Dude, how are we to troubleshoot your system from what I assume is 1000's of miles away? Go back to the installer. It is a shop warranty issue.
Dude I just want to know a logical reason for what happened.

I'm not asking to test my system part by part.
 

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Look, Karnak the Magnificent couldn't diagnose this problem from over the internet, and with no real-time tests available (and, no disrespect, with you the guy relaying data... as has been said, you lack experience or theoretical grounding).

Reversing the polarity on the speaker won't blow anything up. Hooking up the crossover wrong could, making other wiring mistakes could, none of which anyone can see from here.

Sorry you have blown speakers, speakers which are very specifically NOT warranteed (not a failure in workmanship or manufacture, and the amp warranty does not cover downstream damage).

Your shop should be figuring it out, but since you are here, i suspect that you picked a shop who is not helping you with gear you bought elsewhere.

Welcome to the DIY part of DIYMA.
 

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Look, Karnak the Magnificent couldn't diagnose this problem from over the internet, and with no real-time tests available (and, no disrespect, with you the guy relaying data... as has been said, you lack experience or theoretical grounding).

Reversing the polarity on the speaker won't blow anything up. Hooking up the crossover wrong could, making other wiring mistakes could, none of which anyone can see from here.

Sorry you have blown speakers, speakers which are very specifically NOT warranteed (not a failure in workmanship or manufacture, and the amp warranty does not cover downstream damage).

Your shop should be figuring it out, but since you are here, i suspect that you picked a shop who is not helping you with gear you bought elsewhere.

Welcome to the DIY part of DIYMA.
Nicely stated.;)
 

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DC offset didnt kill your speakers. As a signal gets clipped, the power area under the curve increases greatly, and the clipped portions of the wave are basically DC.
 

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One thing blows speakers: too much average power over time.

Dont turn it to the right quite as much.
But me likey to turn to the righty. :)
 

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No they are not, As long as that signal crosses the 0V line it's not DC it's just a square wave. Alternating current can have any waveform.
There is no way in hell these threads will ever stop coming :mad:
quote some BS:
the clipped portions of the wave are basically DC
Dee Cee THIS :rifle:
quote some BS:

DC goes in one , not two directions
 

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No they are not, As long as that signal crosses the 0V line it's not DC it's just a square wave. Alternating current can have any waveform.
Hey man,
Just like I said on CAF the clip from a Digital Amp Like The PDX
will pop a tweeter is no warrning..

also make sure the tweeter was wired into the tweeter loacation on the Xover
if it was on the Mid it would blow very eazy
 

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There is no way in hell these threads will ever stop coming :mad:
quote some BS:
the clipped portions of the wave are basically DC
Dee Cee THIS :rifle:
quote some BS:

DC goes in one , not two directions
Jeez, sorry Hic, I admitted my mistake (assumption)
 

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Well,

First contact Alpine and let them know this occured while using these speakers on an Alpine amp. Then just tell them the speakers just crapped out. You had them professionally installed and want to send them back for repair/replacement. That should be it. Any decent company will stand behind their products and offer any necessary advice to avoid the problem in the future. (I personally think if you're running active that you should attach some kind of passive capacitor to highpass the tweeter @ 1,500Hz or so to soften any discharge anomaly from the amp.
 
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