I drive a 1999 Mustang GT with a mach 460 sound system in it. My fiend tried to help me install a 10' JL Audio sub and a Lightning AUdio 450 Watt Amp on the stock system. He ran the power wire, remote wire, and then ran 4 wires each from the two woofers in the back, the positive and negaitive connectors on them, and then dropped them directly down and into the amp. The sub ran great for about a week, then it just stopped hitting altogether. Turns out the rear passenger side amp blew. Instead of replacing the blown amp, I thought I could just install a new stereo unit and run RCA's directly to my lightning audio amp and it would fix the problem. Well, I bought a Power Akoustic PACD-506 4x40 Watt CD player and installed a premium wiring harness to it, then ran the RCA's from it to my amp. What's happening now is, I'm getting a really bad whining noise out of my speakers now, especially when I rev up my engine. On top of that, the bass on the stereo is maxed out, but the sub is not hitting hard at all, not like it was when I had it hooked to the stock stereo. On my stock stereo, I could not turn the bass up half way before my windows started to flex, so something is definitely wrong. I really need some help getting the system fixed once and for all. I've been second guessing on all of this, and it's becoming rather expensive. If you guys could please help me out, I would most truly appreciate it.

 

it would help if you knew what you were doing.... next time dont screw with stuff you dont understand

your going to have to re-wire the entire stereo, which will cut out the factory amps.

have fun

 

He had no clue, and I regret him doing that. So you're saying I would need to rewire my entire system, to my newly installed head unit I suppose? Is there no way to just install a new head unit but keep the factory amps. I went to a radio shiop and they told me to use a premium wire harness on the stock wiring connector and just run those to my new head unit. The system still runs, just now I get the whining noise and the sub doesn't hit quite as hard, but its bearable for the time being. If i have to rewire the entire system, i'd just prefer to remove the whole mach system as a whole. It's much to complicated, and it's a pain to work with.

 

the whining noise is caused by power and signal wires running near eachother
run power on one side of the car, rca's on the other
make sure rca's arent running next to factory power wires either, when you have to cross them, do so at 90 degrees

pull everything out and rewire it, better yet send it somewhere to be done

 

Yeah take it to the shop and have them rewire it, if your stuff is still good then you will only have to pay for the labor...toss them a few more bones to do it up right. If they are losing money on the sale of their products and time to work on stuff bought from other places they will be less inclined to do a good job so make sure you make it worth it to them and you'll have that system up and running sooner than you would if you had your friend try to do it again. Same thing happened to my intrepid when I had it the whining is exactly as Klap explained...a little too technical for me which is why I always have my stuff done by pros.

 

Just as a side note. When I put in my system the first time in my Stang, I got a whinning noise. I thought, ok no problem I will check the usual suspects. I checked the RCA's I knew I had run my power down one side fo the car and signal on the other, SO I knew that wasnt the problem. I tried new RCA's And it still wouldnt stop. Finally I rechecked my ground connection to the car and found that I didnt do as good a job at making a solid connection. As soon as I fixed that, It went away.
Check this out too.

 

is hart to tell when the car is not here to see what he did but maybe there is a hi/low adaptor because of the factory radio and you don't need this wh a new radio that comes with rca outputs
but it will be better to take everything and start over