Power and RCA's

Ok, for years I have been installing my power wire along the side of the car the battery is on and the rca's on the opposite side. From what I know the reason I have been doing this is because the RCA's or the power wire give off a signal which is roughly 12-18 inches in circumferance and that could make a possible road or engine noise. First question; Is my statement correct? Second Question; If not correct is there a reason to install the RCA's and the power wire on opposite sides of the vehicle?

PS I know that ground problems can also be a factor when discussing noise problems.

Edit:

Second Question: If NOTcorrect.... blah blah

For lack of a long winded explanation, you are correct. Also keep an rca cable away from engine computers etc.

The way i like to do it is running the RCA's right down the middle of the car.

It's just a bit harder since you have to remove one seat, but the only wire that runs down the middle is the e-brake wire.

Basically if you get a good set of cables, and a head unit with high voltage rca outputs, noise from interference shouldn't be a problem.

Not so long winded explanation:

When current runs through a cable i creates a magnetic field around it.

If you run a cable paralel to this field, the field can induce a current flow on the second cable (THis is how transformers work).

It doesn't induce a lot of current, but since the RCA cables go to an amplifier, this small intereference gets amplified ! thus becoming bothersome.

If you must cross RCA's with power wires, at least try to cross them at a 90 degree angle, instead of running parallel.

If you're going to run them parallel, depending on how much current will pass through the first cable, you need to separate them more and more.