Amp output problem

alex81388

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Hey guys. I run a 4-Channel amp from a generic Alpine HU.

I was having problems because after all was installed I would get the "whine" from the alternator. I decided to install 2 GLIs (Ground Loop Isolators) to deal with the whine, and it worked... I no longer have anything but audio... but i lost output to the Rear Right speaker!

in the trunk:
The RCA cable corresponding to RR outputs onto every channel (including RR, but with the whine) just fine, so up to that we're good. However once I put the GLI on that wire... it doest work. Now the GLI will output the LR no problem... in either the white or red ports. So the GLI works fine (i would think). How does it tell the different between the LR and RR RCA cables when they both work perfectly and only output the LR one? No matter if i plug the LR RCA into the Red/white port on the GLI it always works... the exact opposite for the RR.

Here is the GLI I used. I have 2... one for front and one for back. The front one works flawlessly: Radioshack GLI

Thanks in advance!


EDIT:: No matter which GLI I use, the same problem exists only on the RR RCA cable (or the RR input on the amp?)
 

lashlee

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It could be a bad input on the amp. If you have tried all other combinations, bypassing the gli and swapping the rca's like you did would indicate that there is a problem inside. I have seen it in the past where the amp is source of the whine, and eventually leads to other problems and headaches. See if you can try another amp, or hook up some rca's to another car and run into your system.
 

alex81388

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It could be a bad input on the amp. If you have tried all other combinations, bypassing the gli and swapping the rca's like you did would indicate that there is a problem inside. I have seen it in the past where the amp is source of the whine, and eventually leads to other problems and headaches. See if you can try another amp, or hook up some rca's to another car and run into your system.

Hey thanks for the reply.

I orginally purchased a brand new amp (after i had mounted this one and all...) and all the speakers worked but I still received the whine. Also, on the amp I'm using, The inputs all work fine in the absence of the GLIs. However, each GLI works with the front left and right speaker, and the rear left speaker.... Normally I'd be able to rule out what component is the problem but it doesnt' make sense!
 

lashlee

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It dosen't!! The only thing that I could think is to try a different set of rca's that run from the gli to the amp.

Let me get this straight: H/U to amp everything works but whine.

H/U to gli RR quits working

swapping gli same issue

then that leads me to think it's the one component that leads from the gli to the amp.
 
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