Ground Loop Isolator
03-24-2008, 05:05 PM
#1
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Ground Loop Isolator
How does a ground loop isolator work? Does it create a loss of any frequency or sound quality? I was getting an alternator whine and buzzing at idle-it went away, or increased in Hz above hearing range, once I stepped on the gas. It was very annoying, to say the least. The RCA cables I used are a good brand, but the noise went away when I disconnected the front and rear from the amp (the sub amp is noise free). I tried using a different set of RCA wires, and the noise went away. But I did not want to go through the hassle of rewiring the entire car, and rewrapping the harness. By the way, the power wires are on the other side of the car and amp board so I dont think that is the problem. To avoid changing the cables, I tried a couple of ground loop isolators, and they also eliminated the noise. It is a much simplier solution, as long as it is not causing any damage or reducing the quality.
03-24-2008, 05:22 PM
#2
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I have never heard of a ground loop isolator damaging any system components. I am not an electrician but here is what I think I know. A ground loop is caused by two different components sharing a common ground. The noise created by a ground loop is voltage being applied to the common ground by one of the components. This is pretty much out of my field of knowledge so I will wait to see postings by people better equipped to discuss this. In the mean time I will refer you to my signature.
03-24-2008, 05:28 PM
#3
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The package said it corrected situations where the ground for the radio is in a different spot than the ground for the amplifier. But how can it do that without being connected to any grounds itself? I wonder what is inside of it? If it is just resistors, capacitors, etc then it works by eliminating the high pitched sounds, but this could possibly also reduce some of the music you want to hear. This is where I am confused.
03-24-2008, 05:33 PM
#4
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The package said it corrected situations where the ground for the radio is in a different spot than the ground for the amplifier. But how can it do that without being connected to any grounds itself? I wonder what is inside of it? If it is just resistors, capacitors, etc then it works by eliminating the high pitched sounds, but this could possibly also reduce some of the music you want to hear. This is where I am confused.
03-24-2008, 05:48 PM
#5
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I found this explanation on the internet. Based on this, it should not reduce the sound quality at all.
Construction:
A ground loop isolator contains an isolation transformer for each channel. The transformers generally have a 1:1 ratio which neither boosts nor cuts the audio level. The audio is magnetically coupled through the transformer's core. Since DC can not flow the transformer, the DC path is cut and the noise is eliminated.
Construction:
A ground loop isolator contains an isolation transformer for each channel. The transformers generally have a 1:1 ratio which neither boosts nor cuts the audio level. The audio is magnetically coupled through the transformer's core. Since DC can not flow the transformer, the DC path is cut and the noise is eliminated.
03-25-2008, 12:02 PM
#7
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Good luck. This is a common problem for those who add amps and after market audio to their HHR's. It's going to be hit or miss troubleshooting to figure out what's really causing the problem. I had to rewire everything and I still get noise but it comes and goes. Sometimes I can hear my turn signals coming out of my two ten inch subs!
Ng
Ng
03-25-2008, 12:05 PM
#8
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Ng, I cant believe you said that. I had the same intermittant problem. Sometimes the noise would totally go away at idle, other times it was back. I would also get an occasional pop sound when I stepped on the brakes. But, these gound loop isolators have totally eliminated the noise.
If you buy them at Radio Shack, you can return them if they dont work so you have nothing to lose. You also need 2 pairs of female to female connectors.
If you buy them at Radio Shack, you can return them if they dont work so you have nothing to lose. You also need 2 pairs of female to female connectors.
03-25-2008, 12:10 PM
#9
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Ng, I cant believe you said that. I had the same intermittant problem. Sometimes the noise would totally go away at idle, other times it was back. I would also get an occasional pop sound when I stepped on the brakes. But, these gound loop isolators have totally eliminated the noise.
If you buy them at Radio Shack, you can return them if they dont work so you have nothing to lose. You also need 2 pairs of female to female connectors.
If you buy them at Radio Shack, you can return them if they dont work so you have nothing to lose. You also need 2 pairs of female to female connectors.
Ng
