Power Wires And Rca's

yes there WAS merit to this, Now doay with Voltages over 4V there is really not much need, but back in the "good old day" with HU under 1V line Voltage, Noise seem ot come from EVERYWHERE

Also, Advancments in the Shielding of RCA's have been the effects of Increased Line Voltage even better.. Meaning Less noise where Noise would have been rampant

However, As you increase the Amount of Current that Flows through the wire the RF signal generator will also increase, so while you may have no noise ay at 60amp, you get to 160amps you just might

but In most common applications now, with Decent RCA (and by Decent I am not talking $50 Monstor Cables, I run 600 Series Tsunmi for like $10 for a 20footer) there should be no problems

 

I always reccomend it.

The chassis of the vehicle is of course a conductor, but is RFI ever present near a ground wire? It is always the positive that induces the RFI .

While you are correct, a proper install will reduce and likely eliminate noise potential, there is still moisture in the air, bumps to go over, and other things that may loosen or corrode a ground just enough to allow for potential differencials that can and will induce noise. Also you need to consider that many people will shortcut their install, and possibly create noise machines!!!

I always reccomend it considering those 2 facts listed above, and I also do it on my own vehicles. In my Nat I have speaker running up the drivers side, RCAs on the tranny tunnel, and my power is run through the solid frame underneath the vehicle (the frame is a great shield like a shielded wire ) up into the trunk and to the amps. The only place any wires get close to each other in my car is at the amps, and where my left side speaker wire runs under the dash and my RCAs wrap around it leading to the tranny tunnel.

Why go to such great extent? Because, I want every assurance that I will not suffer any issue due to a poorly done install.

On a customers car I will bundle the RCA and speaker up one side, and power up the other, just to be on the safe side

 

I agree, it still has merit, it's simply because you KNOW absolutely for 100% certain that your positive wire is behaving like an RFI antenna... the higher the current flowing, the stronger the signal.

So, if you know that it's a source of RFI noise, why would you intentionally run your RCA's right next to them?

Granted, it is darn near impossible to run your RCA's in a manner that totally eliminates them from running near RFI sources (but I've been pondering the possibilities of "headliner" lately... B)), but it's just not a GOOD idea to run them just literally hugging against what you know is absolutely an RFI source.

As far as the chassis goes, the whole chassis is a ground plane, but the path the current actually flows through as that return path is quite random. So, your RCA wires likely aren't going to be adjacent to that path. But that path also, is an RFI radiator... wherever the heck it is.
That current isn't flowing through the whole chassis, just whatever the path of least resistance is... so the whole chassis isn't an RFI source, if you will.

Sure, you can get lucky... if your head unit and amps are all nicely isolated, and your RCA's are properly shielded, or you aren't flowing much current through the power wires, etc.
But that doesn't mean it would be a "best practice" to run the RCA's next to your power wires, make sense?

 

DC current flows from negative to positive . The chassis is not the return path .

Just giving you a hard time :bye:

 

food for thot?

http://www.carsound.com/UBB/ultimatebb.php...ic;f=1;t=021564

there IS current running through the chassis anyways....
hmmmmm....

oh yeah
i'm sure you all seen dis

http://www.carsound.com/UBB/ultimatebb.php...t=021545#000018
wich is somewhat relevant...

 

Hey, I'm not an electron, I never stood in that line...
And you know me, I'd go against the flow anyway... B)

 

I am a Firm Believer in the " If is aint broke dont fix it" saying


So if how your doing it now works for you, dont change it, no point

Now if at some point you run across a situation where it causes you problem, then that is when I would seek out alteratives

 

^^^

Limited time and money? If it is too limited I will turn it away. I don't need to install anything in a rush, as rushing always leads to bad things. Let's say we run into a noise issue after the install is completed? Moving everything to the other side of the car now is going to take considerably longer, don't you agree? At least now we can eliminate that as a variable and start looking elsewhere for our noise issue .

If it is a high current situation, the induced noise is still being amplified the same amount as the source material (as in a lower current system). A bigger amp means bigger increases in the input signal weather it is source or noise. The amp will not differenciate between the two. The signal to noise ratio being the same will lead to similar results.

I can see what you are saying (and RC is in this link I assume), but that is only if we are considering RFI on the speaker wire, or output. But I personally have no issues with running speaker wire and power wire on the same side. I don't know of any case of speaker wires recieving enough RFI to induce audible noise. And I definately do not know of any speaker wires coming from an amp that will amplify a signal (or the noise in this situation). Of course, if we look at the cost of some wire we should expect it too, huh

By the way, like Mike says, if you have been doing it all along with no issues, that is cool, keep doing it!!! I'm not here to change how you do things, I am simply offering what I do, and giving my reasons why. It is just like my job fixing cars, differant people have differant approaches, as long as the end result is a fixed car, who cares how it got there

 

I think especially in a customer's car, for money, I would run them separately.

If the customer comes back complaining of noise, not only is the troubleshooting time consuming, but because the complaint stems directly off that install (as opposed to something that developed, down the road), all that troubleshooting time would be profitless - you wouldn't charge the customer for that time.

It takes so little time to pull up that extra door sill plate, I'd consider it cheap insurance.

In all cases, having the power wire running right next to your RCA wires will never result in less noise than having them running on opposite sides of the car...
Unless you do throw in some extranious factor unrelated to having them separated or close-coupled... like running the RCA wires past the car's ECU on the other side of the car, something like that.

As far as the shadetree installer grounding it to an unclean, less than ideal location... same deal applies.
Having the power wire and RCA wire located right on top of each other are not going to result in less noise than having them located on separate sides of the car...
Really two unrelated potential causes of noise.

And there's lots more (like the ECU ).

 

well I am going to have to let you guys in on a Little Secret, most shops DO NOT run them seperate

Like I said in my Post, Power Wire Induced noise is UNCOMMON in common installs today with Line Voltages at or over 4v

That is just like Saying Sodering Connections is a MUST DO

While YEs a Sodered Connection is prefered it is not a requirment

 

Ohh and what he is talking about with "profitablity" is very true, unless the Company has a Local Monopoly, the Comptition is so fierce that I have seen Shops having to offer Free Basic Installation on all products,

and even more often they are going to Flat Rate Installs for Basic Installation, say $60 for a amp

so in both these cases, that extra 15min per car, times 10 cars, is ALOT of money down the drain, that is 90% of the cases would have been pointless waste