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Old 12-08-2011, 04:59 PM   #10
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Originally Posted by kwg2371 View Post
1. correct front and rear speakers will be wired in to the existing stock harness(unless you plan on throwing an after market amp to power the speakers)

2. you only need ONE RCA to be spliced in and you can plug it in to either white or red output, it doesn't matter which one its plugged into (just make sure you understand what is positive an negative on the RCA cable)

3. in some circumstances you wont need a resistor (the way I have mine wired as shown in this how to, I don't get any kind of popping noise, most decks now a days have built in sub crossovers to where you can adjust them and there frequencies) you'll just have to take a look at the manual.

the one on my deck is accessed threw the main controls where I would adjust highs, lows, bass and treble ETC. I have the option to adjust from 50 -/+ 6, 80 -/+6, 120 -/+6

my best advice is if you can find someone parting out a junk SVT if they would be willing to chop off the stock wiring plug harness's so you don't have to hard wire directly to the deck
hope this helps
Thanks for the response! I understand what I'm doing now but I still don't get what the difference between your suggestion and me simply splicing my sub + to my red RCA sub output and my sub - to my white RCA sub output.

By using the shield of the RCA cable as ground, you eliminate the cables ability to filter RFI noise. So, if the only difference between the two above suggestions is that I am using a single RCA to run two output circuits wouldn't the extra 30 seconds required to run two RCA cables be worth my while due to RFI filtering ability?

The reason I ask is I have a hard time believing Sony would go through the trouble of putting a red SUB + and a white SUB - on the back of my headunit if all I need is one wire.

If it works it works, I'm just trying to figure out the difference between the two methods.

From what I gather is:

The pre amp outputs don't require hardly any current flow so by using only one RCA I am basically using the minimal amount of wire required. The sub pre amp - will be grounded at all times through the RCA shield circuit and the signal will travel along the RCA core providing sub pre amp +. The amp gets the signal and steps up the current to the magnet and thus runs the sub. If this is true, Ford just wasted their time and money making a dedicated pre amp - wire between the stereo and amp.
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