QuestionThanks for the suggestions Mark. OK, when I hooked up a set of RCA's from the head unit to the Sony amp prior to the speaker short, I was re-using an old set and I got the buzzing noise right away. I went and purchased new RCA's and the noise went away. This was all at low volume. Now that same buzzing is back. I unhooked the RCA's to the Sony amp and the buzzing goes away, so like you said it must be a ground loop problem. The crazy thing is that there was no buzzing prior to the grounding of the speaker. I don't know though, you're the expert. Now that we've narrowed the problem down some, what do you suggest. If the answer is grounding the RCA cables can you tell me how to accomplish that. It was suggested to me before but I don't know how to do that. Thanks for the info. I was really frustrated and now I can see the end.
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First off, I have a 1998 Chevy Silverado 4 Door truck in which I have installed a Pioneer DEH-P3800MP Head Unit. From a Stinger SP680 using 0 gauge cable to a 250 amp fuse I have a Kenwood KRC-91020 amp powering 4 Kenwood KFC-W300S subs and a Sony XM-554ZR amp powering 4 Sony XS-R1641 speakers in the door panels. From the head unit I used Rockford Fosgate RCA cables to provide sound to the amps for the subs and door panels. Now for the problem. After I had everything completely installed I powered it up and everything sounded great, no noise,just clear music. I rolled the drivers side window down all the way with the stereo on and there was a loud "crack" from the speaker. I new instantly that the window must have shorted the speaker out. Upon inspection I found out that the speaker wire from the positive terminal got pulled out and grounded out on the metal window frame. At first I got no sound out of any of the speakers except for a loud buzzing noise. I let the truck sit out of frustration for a couple of days and now I have sound but still that annoying buzzing noise when the stereo is turned down low. None of the fuses were blown on anything. I have checked all of the grounds and they seem to still be connected fine. I was told to ground my RCA's but i'm not sure how to do that and i'm not sure that that is the problem. Any answers that you can provide me with would help me alot. Basically, I just need to get rid of that noise. I hope that I have provided you with enough info to answer my question.
Thanks,
Joe
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thanks for all the background info, sounds like you did things well. Id say we can probably break this problem into 2 possible scenareos.
one is that the shorting of the speaker wire caused some damage somewhere and that damage is what's making the noise.
two is that the noise may have always been there but when you tested it you had it cranked up enough that you didnt notice it or something like that.
either way you may be able to diagnose it by unhooking the RCA wires to the amps. if they still buz with the RCAs disconnected then the amps may have sustained some damage. if the buzz goes away with the RCAs off, then you may have some sort of ground looping problem, something like that, then we can try ground loop isolators or grounding the RCAs etc.
try that first and let me know how it goes
Answersure, to ground the RCAs just take a piece of very thin wire. loosen the ground wire on the amp and sneak the thin wire under it. then tighten your ground on the amp back up again. touch the other end of the ground wire to the outside of the rca cable where it connects to the amp (usually there's a little ring of metal exposed) if you cant reach it, just pull the RCA out just a little so you can, just dont pull them out all the way of course!
try that out and see if it helps with the buz. it can make it worse or cause other problems but shouldnt hurt (like physically).
