I drive a 92 pontiac bonneville with with infinity kappa components up front and kapa 6x9's in the back,they were powered by a garbage legacy amp, two l7's in the back powered by a kx1200.1, and the head unit was a deh 4600. With this setup I had a ground loop problem and i added a ground loop isolator and upgraded car to ground and ground to alt and it left me with pretty much no noise. This is were the funny part comes in I upgraded the head unit to a DEH-P9800BT and interior amp to eclipse xa4000. I initially hooked up everything without hiding all of the wires and the sound was clear so i dropped the ground loop isolaters and the sound was perfect. Leading me to believe the noise I was getting before was due to cheap components. Then I tucked all of the wires away (away from the power) and when I started my car it went back to having a terrible noise through the system. I cant' figure out for the life of me what caused it I didn't touch any grounds or anything. I have tried taking the wires back out and going back to how it was before I tucked the wires and nothing I do is getting me back to that perfect sund I had before. Please anybody and everybody help cause this is really stressing me out?
sounds like you are placing the rcas next to some power wires.
You need to ground the shield of your RCA cable use this picture for a guide the end of the yellow wire needs to be grounded
https://www.bcot1.com/images/rca/asdf.html
If grounding the rca's will fix the problem that still doesn't explain why it worked perfectly without it before.
Pioneer HU's have been notorious for having bad ground problems, do a search on here and you will se what I mean Try and take idiots advice and grounding the rca's.
dont ask just try.. they are right
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I dont care about who has the bigger name in the business... The Bigger the name the Bigger the price. NO BETTER QUALITY!!!