Wait wait...in Scenario #6.....what I meant was, that not only were the RCAs next to the power wire ....they were wrapped around the power down down the whole length of the car.....with no whine.

 

I am taking about the whine that was not there before I installed RCAs and an amp that yes comes on with the car even with volumn down and becomes more evident if I turn the AC on then and as it cycles, as ACs do when volumn is also uo more and driving around - thats all - I was just pointing out that the AC doing its thing adds to the whine - high pitched wine that otherwise increases as RPMs do and more so when AC cycles - you know - you are at a stop light and something about the AC running clicks on and off - I guess its the compressor something

I only mention it so anyone else troubleshooting knows of others experience - I expect it to go away with the new RCAs (I hope)

 

As a final experiment, make some home made unshielded twisted pair connectors. Neat huh? So much for the shielding....

 

I've noticed the same as Nick - haven't had to use the heat / fan in a while but recently i have and the wine is much more prevalant when the fan is on

but hopefully new RCAs will solve the trick

 

I do not have alternator whine in my car until I turn the A/C on. So, in my car, it has ill effects on my stereo. Turning on the headlights at the same time makes it worse, but not unless the A/C is on.

One day I might troubleshoot it, but right now I'm just too lazy.

And, I have an expensive set of Monster Cable interconnects and a 4V preamp CD deck.

 

Steve how did you run your wires? Do you want me to rewire your car for you? I have no whine what-so-ever....

 

It's probably not alternator whine but noise from the motor in the fan Some bypass caps on the fan power leads might cure that.

 

Short response - its the AC not the fan in my case


On my auto, it happens when I turn on the Ac - If I turn on the fan without the AC it does not whine.

I wonder how effective my Knu shielded RCA patch cables will be given that the RCA wires coming from the HU are not so very shielded. Next I will be unplugging the RCAs from the amp to see if the whine persist.

Also this whine occurs when the HU is on Mute and does not increase in volumn when I turn up the volumn muted or not.

I now deem this thread important as others have troubling whine. I never had this trouble without an amp so I guess the trouble is only for us that use the RCA low input I suspect that if we used speaker inputs into the amp - the problem would not occur but we want to use RCA as it is otherwise better quality input if I understand things; I wonder if my sub will whine - probably not as it does not give out high notes

Many of us need a fix because of this in more ways than one

 

ok, here is some info
1. Try not to use Coaxial type RCA's Twisted pair is much better at noise rejection.
2. While cables have gotten much better over the last few years, it is still a good idea to separate the cables. the most import thing is , Do not run the Rca's down the same side as the car harness. the reason is a lot of engine noise is radiated from the existing wires and sneak into the RCA's or the speaker wires. It's also a good idea to keep the power cable for the sound system away form the rca's and the speaker wires as well
3. Grounds.
A good ground, and or power connection is crucial. Run the amp directly to the battery, fused no more than 18' from the battery, and again on the amp side. If you're running thick wire (8ga and larger) the fuses will prevent your car from catching fire in the event you have an accident and the wire shorts to ground.
It's a good idea to run an extra ground wire from the radio area to the amp area. Ground loops can cause noise. Having the entire system grounded at the same point can eliminate this issue.
4. inexpensive amps, eq's and Xover's can can add to the noise issue. Mount the amp to a pice of wood and them the wood to the car. this eliminated a ground loop from the amp.

5. Noise that happens when you turn on the AC or the headlights.
Make sure the ground wire that goes to the block is secure. Check your battery. when a battery starts to go, it can still start your car, but it can be less effective in filtering out noise.

that is the end of today's rant

Mitch

 

All good stuff.

I didn't think about the fact that the fan can be on without the a/c stupid me...that's what I get for living in the desert