Factory head unit want to add amp and sub

Ok i have a JL w1 and a J2 360.2 sitting around i was thinking of putting it in the truck now. I have the factory head unit i plan to upgrade but not in the near future. i know ill need a line out converter to run the RCAs and also a 4ga wiring kit. Here is my question what do you use for the remote wire in this situation? i have put several stereos in but all using after market head units. Where does this wire go will this setup work. Theres gotta be something to tell the amp to turn on and off thanks for any help

 

You can wire it to a switched power source.

 

When I had a system running off of the factory HU I ended up running it off a standard switched power source as suggested above. Only down side is that your amps are turned on even if you are not playing the radio. Having said that though, I never ran into a problem with running it that way. If key was off, amps were off so pretty simple.

Since then I've upgraded the hu etc and it isn't a problem anyway.

I did look at some of the current sensing line out converters. Supposed to work by sensing input signal on the speaker wire inputs and this turns on the power to the remote wire out that you connect to your amps. I looked at this, but have no direct experience with them. I was concerned about the level of input signal needed to activate and what happens between tracks etc. Are your amps cycling on and off in this instance or does the input line have a base residual voltage that keeps the remote wire circuit energized. Others may be able to chime in on real world experience, but for me I felt the direct switched power was best.

Might be worth contacting Crutchfield tech chat on their website and seeing what the current options are. At least would be helpful in making the decision on what you want to do.