Joined: Nov 16, 2001
Posts: 2053
From: Mpls, MN

Power cable really doesn't make a great deal of difference other than: 

Insulation is thick enough 
Guage is large enough for the job 
Insulation is designed for automotive use 
----I.E. won't deteriorate easily from oil, elements. 

RCA CABLE- Now there's a story & a half! 

RCA cable CANNOT affect the sound quality, nor improve the sound with any number of shields. It is not cable of picking up noise unless the insulation is stripped or cut and the cable is physically touching the body of the car. (let's leave 'shielded' cable alone for a minute) 

I'm going out on a limb here, but I HIGHLY DOUBT that if you run your RCA cable on the same side right next to your Power cable, it will induce noise. This is assuming that you don't have RCA cable with that metal foil 'shield' which is known to pick up noise. So much for 'shielding' huh? 

Just plain RCA, Gold is optional. 

CONNECTORS 

Gold is good enough...actually, silver is good enough. Silver has a higher flux capability than copper, but unless you are using less contact area than you'd need with copper, Silver is unnecessary. Gold, and Platinum are better conductors, and even more unnecessary. But they are prettier, so if that's important to you, go right ahead.