islingtonaudi

perhaps someone can simplify it for me. Avincar wrote a detailed explanation a year or so ago on stray noise in one's system and he obviously has knowledge in this realm. My problem is this:
my system has noise only when the system is on, it doesn't seem to be affected by engine revs but it is quite noticable.
What I was confused about is how to ground the input wires as he mentions and at what location..? I'm using an older but clean a/d/s amp for mids/tweeters and an Alpine V12 mono amp for the sub. Do I need to hook an alligator clip to the RCAs? At what location and do I hook the other end to the ground wire coming from the amp or somewhere else? Thanks for the advice, the installer of my HU says older units like mine (a mid-90's Sony) have problems with noise that can't be cured but I'm wary of this dismissive attitude. Any help/clarification is appreciated!

MacSub

and ground it to the chassis of the car?
The standard Audi earth wire on the black power loom is pretty feeble, so I'd start with making sure the HU is well grounded, as if it isn't it doesn't matter what you do at the amps or the wiring, it will have no effect.
With that sorted then ensure the amps are well grounded using the shortest possible ground leads.
If you still have issues then check the quality of the RCA's, are they just cheap & cheerful? Invest in some decent ones.
Also are they running down the same side as the power cable? While good quality RCA's should sit quite happily alongide the power to the amp you can get interference from the 2.