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CaptainPioneer wrote:^^^Bad ground

my meteter measures the same potential between the power and ground lines at the amp that it does at the battery, can this be true if it's a bad ground?

Did u create a new hole to ground to or are you grounding to a chair or something? I have found that most of the time when i create a new grounding spot i always grind away all of the paint and everything and then use petroleum jelly on the areathat i am grounding to to keep it nice and electrically sound

this might seem like an obvious, but did you check the ground wire itself for line breaks, shorts, connectors?

CaptainPioneer wrote:Did u create a new hole to ground to or are you grounding to a chair or something? I have found that most of the time when i create a new grounding spot i always grind away all of the paint and everything and then use petroleum jelly on the areathat i am grounding to to keep it nice and electrically sound

I just used a bolt sticking from the frame, i tested it, and between the amp power, and the bolt, i measure the same potential as that of the battery. I ground the area around the bolt all the way to metal, and then some more, tested the bare metal in the same way, and it measured the same potential.

"this might seem like an obvious, but did you check the ground wire itself for line breaks, shorts, connectors?"

The ground wire appears fine, there's only one connector, and it's connected to the grounding point, the bolt i mentioned above. I've tested potential between the amp positive and the end of the ground, ground at the amp, and grounding point, all read the same potential...so, unless my meter is utterly useless, I don't know what to do next. If I feel up to going out in the heat today, i might try another grounding point.

Sounds like the problem is in the amp, but try another grounding point (sounds plenty good enough though).
As far as the tester, I'd still go buy a new one. Local hardware shops have sales on cheap ones that work just fine for $20 all the time.

Yea, if you have access to another amp also, swap it and see if the noise is still there. Just gotta keep isolating variables.

solacedagony wrote:Yea, if you have access to another amp also, swap it and see if the noise is still there. Just gotta keep isolating variables.

I know, I really hope it isn't the amp, but, I need another meter to be sure. I don't have access to another amp, and I don't know anyone who owns one, so, that would be tough.

the only other thing i can think of is if u have isolated everything go to an audio shop and have them test it to see if there are any problems... It will get u further than anything else i can think of

CaptainPioneer wrote:the only other thing i can think of is if u have isolated everything go to an audio shop and have them test it to see if there are any problems... It will get u further than anything else i can think of

i think I'm going to have to do this...or find someone who has a friend who has experience in this area. I've basically limited it to the amp ground, or the amp itself. Problem is, there are no other bolts in the frame other than the one I'm using, and I don't have the tools to make another spot. Then I get to figure out how to get rid of the alternator noise.

edit:
Is there any way that the remote wire could carry the noise? Or is that a ludicrous idea?

I may have solved the problem...well, maybe it's a work around? The Eclipse has an input voltage adjustment nob. My HU puts out 2.5v, according to the manufacturer. When i set the nob to 2.5 i get background noise. When I set the input voltage to around 7v, I get no noise. The downside here, is that at the higher setting, I have to turn the volume up to achieve the same loudness as when the input voltage nob is set to 2.5v.