wire size FYI

[chris229 10+ year member]

Originally posted by Steven Also CHRIS229.

 

Even the amps idle current can induct a noise into the signal wires. most amps have an idle current between 500mA and 5A, that could induct a significant amount of noise into a system thats recieving 2-4volts of input

if you believe that the signal wire inducts noise from the power wire what do you do about the ground? As it has the same amount of current in it as the power wire? how do you keep away from the car body?

 

[chris229 10+ year member]

Originally posted by rco8786 Go run your power wire next to your RCAs

thank you----good advice

 

[Steven 10+ year member]

Induced noise is noise that is inducted into your sugna wires by a nearby changing magnetic field. ie - the field around the power wire leading to your amplifiers.

ANY changing magnetic field can induce an electric current into a wire, hence why generators and alternators work. They either spin a field around a coil of wire, or spin a coil of wire inside a field.

Now you run your power and signal wires next to eachother. The magnertic feild surroundig the power wire changes EVERY time the amplifier needs a different amount of current, whether the demand has increased or decreased. This changing magnetic feild interacts with your signal wire and induces an electric flow through the wire. The amplifier picks up this electric flow and amplifies it. The amplifier now needs more current, to amplify this induced signal, which causes the amplifiers current requirements to change. More, or less, current flows in the power wire. The magnetic field around the power wire changes, inducing more, or less, electric flow in the signal wire. See a pattern.

Induced noise can be caused by running power and signal wires next to each other.

Now I know what one of you is going to say: HOW ABOUT THE GROUND? how do you keep your signal wire away from the car itself?

Simple - you don't.

For the amount of area the cars body takes up, the actual current flow through the small section that your signal wires are running along is barely existant - less than .001mA and creates a magnetic field only strong enough to pick up a molecule of dust, hardly enough to induce noise into a wire.

Just for a test, if you want, take a signal wire and wrap it around your alternator. Now start the car and measure the voltage fro one end of the signal wire to the other. Chances are you'll find that there is a current being induced into the wire. Probably greater than 6 volts. Now tell me that your power wire cannot induce a noise into a signal wire!

I know the laws of physics, electricity, magnetic fields, and EM radiation

 

[Steven 10+ year member]

Oh yes. And the test - I performed all my tests with the stereo running at full power producing over 1500watts of power

 

[chris229 10+ year member]

Originally posted by Steven Induced noise is noise that is inducted into your sugna wires by a nearby changing magnetic field. ie - the field around the power wire leading to your amplifiers. puting the wires parallel to each other doesn't really give you a high flux density plus the field isn't changing that much. When it is changing more the signal is SO LOUD you couldn't even hear the little noise it makes

ANY changing magnetic field can induce an electric current into a wire, hence why generators and alternators work. They either spin a field around a coil of wire, or spin a coil of wire inside a field.

yes they do induce current into a wire BUT this can't be compared to 2 paralleled strait wires. The reason why is in those designs the wires are coil the give very high flux densities and the spun at very very high speed to pass the high densiy fields through the wire

Now you run your power and signal wires next to eachother. The magnertic feild surroundig the power wire changes EVERY time the amplifier needs a different amount of current, whether the demand has increased or decreased. This changing magnetic feild interacts with your signal wire and induces an electric flow through the wire.

The signal wire isn't coupled well enoungh to have an effect at low current

The amplifier picks up this electric flow and amplifies it. The amplifier now needs more current, to amplify this induced signal, which causes the amplifiers current requirements to change. More, or less, current flows in the power wire. The magnetic field around the power wire changes, inducing more, or less, electric flow in the signal wire. See a pattern.

no --------- the signal wire isn't passing though enough flux density for this to happen at low current

Induced noise can be caused by running power and signal wires next to each other.

nope-------

Just for a test, if you want, take a signal wire and wrap it around your alternator. Now start the car and measure the voltage fro one end of the signal wire to the other. Chances are you'll find that there is a current being induced into the wire. Probably greater than 6 volts. Now tell me that your power wire cannot induce a noise into a signal wire!

---------ummm this test has nothing to do with runing your power and signal together

I know the laws of physics, electricity, magnetic fields, and EM radiation

you do----------//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif k----- then why are you arguing this? and how come you seem to think 100A tough 10gauge wire equals a voltage drop of .01V

 

[maylar 10+ year member]

Originally posted by Steven Induced noise is noise that is inducted into your sugna wires by a nearby changing magnetic field. ie - the field around the power wire leading to your amplifiers.

The keyword here is "changing". You stated that steady-state idle current can induce noise. Nope.

ANY changing magnetic field can induce an electric current into a wire, hence why generators and alternators work. They either spin a field around a coil of wire, or spin a coil of wire inside a field.

Another keyword - "coil". Faraday's Laws of Induction state that the induced voltage is proportional to the change in current and the number of turns of wire coupling the field. Two straight pieces of wire have very little inductance. There is no magnetic core to concentrate the field between conductors. In fact, the steel floorboard of a vehicle will have the effect of diverting the field to ground.

Now you run your power and signal wires next to eachother. The magnertic feild surroundig the power wire changes EVERY time the amplifier needs a different amount of current, whether the demand has increased or decreased. This changing magnetic feild interacts with your signal wire and induces an electric flow through the wire. The amplifier picks up this electric flow and amplifies it. The amplifier now needs more current, to amplify this induced signal, which causes the amplifiers current requirements to change. More, or less, current flows in the power wire. The magnetic field around the power wire changes, inducing more, or less, electric flow in the signal wire. See a pattern.

LOL. Did you make that up?

Just for a test, if you want, take a signal wire and wrap it around your alternator.

Apples and oranges. No one wraps their power wires into a coil. THAT would be a problem.

I know the laws of physics, electricity, magnetic fields, and EM radiation

You need to study some more.

 

[SpeeDFX 10+ year member]

Who hear actually runs their signal wire with their power wire? Please tell me how the system is..just wondering thats all

 

[maylar 10+ year member]

Originally posted by SpeeDFX Who hear actually runs their signal wire with their power wire? Please tell me how the system is..just wondering thats all

I do, actually. My power wire runs alongside the rear channel RCA cables, along with the speaker wire for the left door. No interference that I can perceive.

 

[chris229 10+ year member]

Originally posted by SpeeDFX Who hear actually runs their signal wire with their power wire? Please tell me how the system is..just wondering thats all

I do-------- most people who aren't caught up in BS do to

 

[Alaxan 5,000+ posts]

Originally posted by chris229 I do-------- most people who aren't caught up in BS do to

I don't but not for interference reasons I do because I had all of my interior pulled out and it was easy enough to install and run the wiring without it. Yes to the smallest degree possible you can get a certain amount of humm or feed, but if properly run and grounded it should be more than fine.

 

[chris229 10+ year member]

Originally posted by Alaxan I don't but not for interference reasons I do because I had all of my interior pulled out and it was easy enough to install and run the wiring without it. Yes to the smallest degree possible you can get a certain amount of humm or feed, but if properly run and grounded it should be more than fine.

trust me it not possible with an amp's power wire------- doesn't draw enough current for the webber/sq meter density of parallel wires
grounds don't cause noise either

 

[Steven 10+ year member]

Ok you guys. We all pointed out valid points. In the end none of us can absolutely for sure that running the signal and power wires together will cause noise. A friend of mine pointed out something that we ALL forgot. Most RCA cables are shielded, this will help to prevent inducted noise. But you can't argue the fact that many people have had problems with noise being inducted this way. Also, I never said that it will cause noise, just that it might.

I've had this problem, and talking to installlers at local shops, they've had quite a few people bring systems back because of noise being inducted from the power wire. Move one of the wires to other side of the vehicle and the noise was gone. So I'll finish this post by saying:

Running your signal and power wires may, but not necessarily will, cause noise problems. For people just starting out - why take the chance - keep them separate and avoid a possible problem. Also running them separate makes it easier to organize your wiring. Power on one side - Signal on the other.

 

[Steven 10+ year member]

Another thing chris..

what causes alternator whine. Everyone has always told me a bad ground will cause it. But you seem to think that grounds don't do anything allow a return path for the current.

I've heard bad grounds can cause:

1. alternator whine

2. noise (buzzing or hissing)

3. amplifiers to go into protect mode

Without a good amplifier ground the connection is weak and introduces a resistance into the amps power system. As EVERYONE knows resistance = Voltage drop = Loss in amplifier power. This resistance can fluctuate with vibration. A fluctuating resistance will cause the voltage at the amplifier to fluctuate which can introduce alot of noise into the system.

A weak alternator ground will cause the charging system to be substantially weakened. The Alternator has to work harder to maintain charging voltage and will have a premature death.

A weak battery ground - well lets just say this is bad, very bad. It causes slow cranking, more boost starts needed, and our favorite enemy, a voltage drop.

Well obviously we don't want any of these, so we tend to make sure all of our grounds are clean, tight, and reliable.

 

[MikeofTulsa Moderator]

hate to tell you this....but in this case you are wrong and chris has the facts that proove it......which will probably be here shortly...heh

 

[chris229 10+ year member]

Originally posted by Steven []Ok you guys. We all pointed out valid points. In the end none of us can absolutely for sure that running the signal and power wires together will cause noise.

yes we can --- in the same sense know that 1volt across 1 ohm will have 1 amp of current

A friend of mine pointed out something that we ALL forgot. Most RCA cables are shielded, this will help to prevent inducted noise.

your friend is wrong and noise in this frequency range can't be shielded against very easy---- lets just say it would take a couple meters of solid steel---- which weighs a couple tons. It would be more effective to route the wires away from the noise source

But you can't argue the fact that many people have had problems with noise being inducted this way. Also, I never said that it will cause noise, just that it might.

inducted noise can happen ----------- just not from the AMP's power wire beleive me no one has had trouble from a power wire----------- even if they thought they did

I've had this problem, and talking to installlers at local shops, they've had quite a few people bring systems back because of noise being inducted from the power wire. Move one of the wires to other side of the vehicle and the noise was gone. So I'll finish this post by saying:

if they believe that then THOSE are the people you want to stay away from----- when doing work on your car

Running your signal and power wires may, but not necessarily will, cause noise problems. For people just starting out - why take the chance - keep them separate and avoid a possible problem. Also running them separate makes it easier to organize your wiring. Power on one side - Signal on the other.

do as you want-------- hell I just read a post somewhere about a guy who runs his power wire through steel pipes and run his signal wires through copper ones--------------- for noise purposes //content.invisioncic.com/y282845/emoticons/banghead.gif.8606515f668c74f6de0281deb475b6fd.gif