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PassatVariantPunk said:
Came with the 4ch amp I just got. Are these going to be necessary for my install?

So excited
Can't wait to get this hooked up.
No, if you don't have anything faulty in your install you won't get noise, and if you do you'd be better advised to resolve the problem than to mask it. In a properly installed system with no faulty components you won't have noise.

Also, some people will tell you such things as running power and signal on the same side of the car will cause noise, again the same applies. Running power and RCA on the same side will not harm anything at all, but you might find it easier to run on opposite sides for space and/or easier cable routing.
 

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^^^^FINALLY!!!! I thought I was the only one knew you could run power and signal on the same sides of the car! I think I just wet myself.....

Seriously, everything he said is DEAD on.
 

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Discussion Starter #4
Ya I been hearing that cable cross contamination stuff. If I was running a military top priority HAARP project then maybe I would be worried about this..but I am running a mildly powered system in a station-wagon.

Cool.

And oh, mods always seem to win. My MDF DIY Box sucks. StlB5 just recieved his first Variant Stealth Box customer. :whistle:
 

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Discussion Starter #5
reborg said:
No, if you don't have anything faulty in your install you won't get noise, and if you do you'd be better advised to resolve the problem than to mask it. In a properly installed system with no faulty components you won't have noise.
What are some faults which would cause pollution of the sound? You mean a literal ground fault? Or what else should I be mindful of. I guess don't hold speaker wires by screwing them into the body would be one?
 

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PassatVariantPunk said:
What are some faults which would cause pollution of the sound? You mean a literal ground fault? Or what else should I be mindful of. I guess don't hold speaker wires by screwing them into the body would be one?
It could be a bad ground in the HU, damaged insulation on the RCAs, bad ground in the amp, shorted speaker and the list goes on.
 

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my power and signal are on opposite sides for the following reason: if for some reason, the alternator starts getting noisy (and it DOES happen), then your power system could pollute the power supply on the amp. there are two ways to combat this; the first is to run the power on the other side of the car (yea, yea, I know...). the other is to ensure there are lots and lots of twists in the signal cable - the theory there is it would cancel out any induced signal from a polluting source. on submarines, we always make sure we run the sonar low-level signal cables far away from the power cables. ya never know how the nasty noise is gonna sneak in there...
oh - and it is always a grounding problem that causes most noise, btw.
 

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JayTheSnork said:
my power and signal are on opposite sides for the following reason: if for some reason, the alternator starts getting noisy (and it DOES happen), then your power system could pollute the power supply on the amp. there are two ways to combat this; the first is to run the power on the other side of the car (yea, yea, I know...). the other is to ensure there are lots and lots of twists in the signal cable - the theory there is it would cancel out any induced signal from a polluting source. on submarines, we always make sure we run the sonar low-level signal cables far away from the power cables.
How do you run the cables away from the car's chassis?


ya never know how the nasty noise is gonna sneak in there...
oh - and it is always a grounding problem that causes most noise, btw.
I can count the number of times a bad ground has been the real cause of noise in a car system I've diagnosed on one hand. Seriously.
 

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Discussion Starter #9
And he is talking military sonar systems on subs. So like I was saying, maybe a considerable, real concern for a HAARP project but nothing of much concern for my low power system.

I agree with ya JTSnork but here I am going to take Paul's wisdom and runthe wires on one side.. if I can.. I don't think I will run out of room.
 

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all I can say is this - I have a 14 y.o. who will probably get this car at some point. there's no telling how she will treat it or care for it later. but I do know this - no matter what happens to the electrical system, it won't get noisy on the signal lines.
 

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quality_sound said:
How do you run the cables away from the car's chassis?
if the problem were due to a noisy electrical system, it wouldn't be the chassis that causes the problem. it would be the electromagnetic fields SURROUNDING the positive power cable that would most likely be the culprit.
those can be induced into the signal cables if ran side by side with the power.
 

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JayTheSnork said:
if the problem were due to a noisy electrical system, it wouldn't be the chassis that causes the problem. it would be the electromagnetic fields SURROUNDING the positive power cable that would most likely be the culprit.
those can be induced into the signal cables if ran side by side with the power.
i'm not saying the chassis itself would be the problem. I'm saying the current running through it would be the problem would be. Whether it's the power or ground cables, there's still 12Volts running through them.
 

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I don't disagree about the fact that 12 volts of electricity wold be running through the chassis or the positive power cable or the ground cable. what I'm saying is, there would be an electromagnetic field surrounding the power cable that would be collapsing and expanding at a rate coincidental with the frequency of the noise on the power line. it would also surround the chassis, BUT the chassis is much larger than the power cables, so the density of the magnetic field is different on the chassis (less dense) than it is the power cables (more dense). the propensity of noise to be generated into a signal cable in such a scenario would be greater from the power cables than the chassis.
therefore - I run the signal cable on the opposite side of the car. you can do what you want. ;o)
 

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JayTheSnork said:
I don't disagree about the fact that 12 volts of electricity wold be running through the chassis or the positive power cable or the ground cable. what I'm saying is, there would be an electromagnetic field surrounding the power cable that would be collapsing and expanding at a rate coincidental with the frequency of the noise on the power line. it would also surround the chassis, BUT the chassis is much larger than the power cables, so the density of the magnetic field is different on the chassis (less dense) than it is the power cables (more dense). the propensity of noise to be generated into a signal cable in such a scenario would be greater from the power cables than the chassis.
therefore - I run the signal cable on the opposite side of the car. you can do what you want. ;o)
I agree that the field would be less dense, but it's still there. THEORETICALLY you'd be right. In PRACTICE I'm right. Hundreds of installations can't be wrong.
Man I miss these good debates on the newsgroups....
 

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WOW 2 people with good points that present them well and in a controlled fashion...priceless. Hey maybe JayTheSnork can take some headache away from QS.
its only a matter of time before we see topics like this:
"Help JayTheSnork my subs sound awfulllll!!!"
 

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guy022077 said:
WOW 2 people with good points that present them well and in a controlled fashion...priceless. Hey maybe JayTheSnork can take some headache away from QS.
its only a matter of time before we see topics like this:
"Help JayTheSnork my subs sound awfulllll!!!"
I dunno about always presenting them well. I always try to NOT practice "sledgehammer diplomacy." ;o)
and I dunno about taking away some of Paul's headaches, either - I'm the theoretical guy with the BSEE and work on projects that are usually much bigger headaches than the ones Paul slamdunks for a score.

I can only provide advice that's within my realm of experience.
 
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