Need a little bit of help here. Trying to get rid of alternator whine. I bought a ground loop isolator, connected at the amp, still have the whine. Connected at the head unit, still have the whine. Switched to a set of RCA wires that are installed but not being used at the moment, the whine kind of went away, it was still there just not as loud. I am thinking that it is the RCA wires and the amp. But I am not totally sure about which one it is or both.

 

Disconnect the rca's and see if you still have the whine. If you do then you have a grounding problem. If it goes away the try rerouting the rca's away from any power source in the car.

 

All power wires areon the oppisite side of the car as the RCA wires, so I know that is not the problem.
The thing is this. Up until today there was no problem at all. I took the door panels off to sound deaden the doors and then all hell broke loose. Speakers poping and crackling, amp went into protect mode even. Then after like 2 hours messing with the speaker wire to every speaker, got the poping and crackling fixed. Put ingnition in acc position and it was a little crackly. So I checked the ground and power wires. The power wire was looking a little beat up, so cut the wire and stripped the insulation from teh wire and reconnected the power wire. Tomorrow I will check out the unplugging of the rca wires and see it is still there when the wires are not plugged in.

 

Okay unplugged RCA wires, noise gone. I am going to try to reground the headunit in a different spot. Since right now it is grounded on the stock mounting bracket, hopefully that will fix it. I know it is not the power wires since they are on the passenger side of the car and the RCA wires are on the driver side of the car.

 

do you have an amp powering your interior speakers? or are you using the 7551 harness?

 

Yes amp powering interior speakers, yes I am using the correct harness.
Took the car up to Syndicate Automotive Concepts, had them take a peak at it. They told me that the amp is the problem. So it looks like I need to invest in a different amp. Had a Crunch 900.4 in the garage, so I put it to use. When I get back from Okinawa I am going to get a higher amperage alternator though. I put the HCCA 12.2 in today and that suck needs plenty of power, but damn I think it might damage the car though. Hits hard, low, and loud. I have some major rattling going on in the rear deck area though. I need to get that taken care of. Took car of the whine for now though, had to turn the gain down really low. So there is barely anything going to the interior speakers. But I can still hear them though. Just need to take care of the rattling issue with the rear deck, get a better 4 channel, and a higher amperage alternator. Any suggestions on the alternator?

 

Well until you get your alt whine sorted out I don't think you should invest in a new alternator because that might make the whine worse. So did the techs actually test you amp or just look at it? you should really test the ground on the amp. if you have a multimeter set it to ohms place one end on your trunk latch and the other on the place you have your ground if you have more than a couple ohms of resistance... it's a bad ground - ideally it should be 0-1 and make sure you don't have a loose ground if you can spin it that's no good - either toss a lock washer on there or use a slightly larger screw or both.

 

First off, almost any shop is going to tell you its some piece of equipment, so they can sell you a new one. (Our sales guys do this ALL the time). Granted the customer usually gets a better amp and I fix their noise issue, but they really only needed an install change, not a new piece of equipment. Anyway, I digress...

Judging from the fact that the whine is gone when you unplug the RCA wires, I would likely say its not the ground that's causing it. What kind of RCA's are you using? Are they shielded? If so, and you feel comfortable with a soldering iron, try connecting the shield (NOT EITHER OF THE TWO TWISTED PAIR WIRES) to the car's ground. This will prevent the shield from acting like a 12ft long antenna picking up noise and transferring it to your signal.

Next, if that has no effect, try switching out your amplifier with the one you have in your garage. If the whine goes away, it was your amp. If its still there chances are the problem is in the source end of your system. Try checking the ground on the HU. Our radios, like all Nissans, are grounded through the antenna wire. Run a new ground wire for the radio. If you still have the problem, try swapping the head unit around. One of these thing should fix the issue.

 

Try swapping out for different RCA's. You don't necessarily have to run the power wires and RCA's away from each other. I've always ran them together and haven't had issues. Some people do.

If you do and you run them on opposite sides and still have a problem, then like I said, try different RCA's. If you still have the problem it can be a variety of things. Sometimes it can be the amplifier itself.

If you didn't have any issues prior to the audio install, then I would say it's not your alternator and getting an higher output alternator will not solve the problem.

 

Since you quoted me I guess you're agreeing with me?

Another thing you can try is to not ground the headunit up front. Disconnect the ground at the headunit and run it right to where the amp is grounded. That will eliminate a ground loop problem if there is one. I'm in the car audio business and have been for the last 20 years and alternator whine is always either a bad install or crap equipment. A good install with quality equipment should never have noise in the system.

 

Not necessarily. Pioneer decks are known to have issues. Although this isn't the case in this situation, bit if someone using a Pioneer deck is having alternator whine then wrapping some speaker wire around where the RCA's plug into on the back of the deck usually solves the problem.

But I agree, if you have alternator whine it is pretty much equipment or install. First thing I would do is try running the RCA's away from the power wire as that helps sometimes, and the second would be to use different RCA's as some RCA's may not have adequate shielding.

 

Since Pioneer is known to be crap that just proves what I said. If you use quality equipment and the install is done right you won't have alternator whine.

 

I've known them to do it on the 880 PRS, I wouldnt say that deck is crap. It's actually a pretty good deck.

 

I guess that depends on your definition of good. Considering how cheap the Pioneer's are how good could they possibly be? Personally I've always been an Alpine fan. I've always had Alpine in my own car except for one car that I went with Eclipse, but that was about 15 years ago before Eclipse went to hell as well. The new Kenwood Excelon stuff is nice stuff too.

 

Combined with the P9 they are pretty good. I myself haven't used them. I too have used only Eclipse and Alpine. One of my favorite decks is the older Eclipse decks, I specifically had the 8443. I had the CD 7000 but I did not like it all that much.

The last deck I used was the Alpine W200. I won't go with the W205 since it doesn't have the graphic EQ, and I used the H701 so it was very helpful to have that graphic EQ. I may go with the W505 when I do my audio setup, but if not, I'll stick to the W200.

There's a few other decks I'd go with if I had the choice, like Denford, Denon, Nak, a couple older Alpines, Clarion DRZ, but as far as new products go, Alpine and Eclipse for me. I just dislike that the Alpine decks have such low pre-outs.

I haven't used the Excelon units, but I've heard they have an abundance in amenities and display is real nice on them.