pentavolvo

i doubt running a ground will fix it, but try running ground to oem amp

otherwise i would try the rca fix i linked

philip_g

I tried the RCA fix and it actually made it worse. I disconnected it tonight and it's probably 60% better. I'll try to ground the OEM amp tomorrow.
I had all four RCA's grounded together to the same ground as the HU, it got worse, I tried a temp cable to the bat negative and it was just as bad so I pulled those out. I also tried connecting them to the Z2 chassis, no change.

I could try better isolators ifgrounding the factory amp doesn't help.

pentavolvo

i wonder if the isolators combined with the ground fit cancel eachother out or something

with that said i have never had noise on a single c6 with aftermarket unit

philip_g

there are so many variables in the system who freaking knows.

could be a bad GMCO, a bad HU, a bad amp, some crappy wiring that I did, all I know is that if I have to take the dash apart one more time
I thought DC'ing the RCA grounds had knocked out all of the alternator whine so I put it all back together and it's BAAAAAAAaaaaAAACK.

philip_g

so after:
grounding the RCA's at the HU (made much worse)
grounding teh RCA's to the HU chassis (same)
grounding the HU chassis to the battery (same)
routing all the system grounds to one location (the battery -)(same)
grounding the factory amp (no change)

all I can think to do is since the problem started when I switched from speaker level outs to low level, get a quality line level converter and wire it in, I can't think of any other simple solutions.

philip_g

a peripheral 4ch line level convertor fixed the alternator whine, I ditched the ground loop isolators, don't need 'em anymore.
there's still some base level hiss but it's not that bad, maybe the factory amp is crap, I don't know.

Hey do your back speakers sound really "tinny"? I can't remember if they sounded crappy before or not, doesn't matter as you can't notice anyway.

Anyway, I've ome full circle only to land right where I started

philip_g

god dammit.

So I had this problem with my 07. I recently bought a '10 with almost the same setup, just a newer AVIC H/U and whaddayaknow? HISSSSSSSSSSS

crAzy

Im having the whine and slight hissing in my 06 Z with aftermarket speakers/amp. Its annoying.

philip_g

It is isn't it? I think I'll just run an aftermarket amp and subs and do away with the factory everything

markcz

Try putting one of THESE between the car plug and everything you have powered by the oem 'radio' fuse. For $10 and an hours work it's worth the effort if it works

philip_g

the whine isn't alternator noise, it's present even with the engine off.

crAzy

I found my fix for alternator whine and hiss. It was the (-) ground being on the battery terminal. So I moved it to a chassis ground and fixed everything. But doesn't stop there lol. My amp is bad. Overheats with just my rear speakers plugged in.

philip_g

for the HU or the amps?
My assumption is the HU is grounded through the wiring harness, but I seem to remember re-grounding the last car and not seeing any improvement, I'll check it out though

Rayzzz

Make sure you have all your speaker wires and RCA's are ran separate from other wires. I tried all kinds of stuff and then separated the wires and problem gone.
THANKS RAYZZZ MY CORVETTE LIKES MY MONEY