Alt whine (I did search)

[Shugarra 10+ year member]

Okay, I've always had a problem with alt whine on my front speakers. I've just lived with it because it wasn't too bad and I could just turn up my music and drown it out. Well recently it started bugging me so I decided to do some research.

I've tried pretty much everything except for grounding my HU at the same place as the amp ground. Last week I did a bunch of ground stuff as I read that was the cause of 99% of the alt whine problems. I re-sanded everything and tried many different ground points and no luck.

Today I decided I'd try some new rcas because I've heard those have helped some people. I went to my local shop and picked up a pair of Ixos A700 rcas (a higher end set) tried it out and the whine got worse. I took those back to the shop, hoping maybe they could help me out. We took out some Stinger Hypers just to do a quick test to see if it was the rcas and the hypers completely eliminated the whine. So we tried another couple pairs of the A700 and then a set of the A600s all the same thing. Then we took the Ixos rcas into their sound room and plugged em in. All of them were causing horrible noise just by plugging them in.

Anyway they let me trade straight up for a pair of Stinger Experts and I figured since the lower end stingers solved my problem the Experts ought to do even better. I took them home to install (stupid me) and I think the experts could very possibly be worse than the Ixos ones. By the time I had that figured out it was time for me to go to work and I didn't have time to take them back.

This kind of says to me I do infact have a ground problem but it begs the question, why did the Hypers work? I do plan on going back tomorrow and maybe just getting a set of hypers but if anyone on the board has any other suggestions I would really appreciate them. I wasn't able to listen to my car today because the alt whine was so bad //content.invisioncic.com/y282845/emoticons/crying.gif.ec0ebefe590df0251476573bc49e46d8.gif Thanks!

Mike

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[BDIDDY 10+ year member]

My amps were grounding through the RCA's and my dad got out the meter and found out the CD player wasn't grounded. And the CD player not being grounded was causing the whine...

You can get a ground loop isolator that might help....Just go back over everything..

 

[Gilliz 10+ year member]

http://www.carstereo.com/help/Articles.cfm?id=71

 

[Shugarra 10+ year member]

http://www.carstereo.com/help/Articles.cfm?id=71

Read that already, but thank you.

I will definitely go over it again to make sure everything is grounded well. Might have to try the ground loop isolator but it seems to me that I read you might lose frequency response with those? Maybe I'm just confused. Thank you though.

Mike

 

[maylar 10+ year member]

Read that already, but thank you.
I will definitely go over it again to make sure everything is grounded well. Might have to try the ground loop isolator but it seems to me that I read you might lose frequency response with those? Maybe I'm just confused. Thank you though.

Mike

I feel your pain. Alternator whine sucks. I'm no expert - still dealing with this myself - but I'll tell you what I've learned. "Ground loops" can cause alternator whine. That's why everyone will tell you to double check your grounding. The problem comes from the HU and amp being at different ground potentials.
RCA cables have a shield around them. The shield is grounded at the HU end just by being plugged into the jack. On MOST amps, the input jack is isolated from ground, but on some it's not. By connecting the RCA's between them you connect the amp and HU grounds together. If there's a difference in potential, current can flow on the shield and somehow that causes whine.

Unplug the RCA's from the amp and if it gets quiet, that's probably the problem.

Some RCA's are made with one shield end isolated - that end always goes to the amp. That's how changing RCA's can sometimes cure the problem. I helped my noise problem a whole bunch by peeling the shield back (disconnecting it) from the RCA plug at the amp end.

Other people run the HU ground wire all the way back to the amp. On my system that won't work because the HU is grounded through the case to the dash. Bummer.

Ground isolators are a last resort - yes, they can affect frequency response.

 

[ngsm13 5,000+ posts]

yeah, keep us posted if u actually solve the problem. I am having the exact same problem...usually just turn it up to drown out the little crackle....but i might just ground the HU all the way back to the amps...i dunno, but it is really starting to piss me off. peace

NG

 

[Shugarra 10+ year member]

Well, went back to the shop and got the set of Hypers, installed them at the shop and didn't notice any whine. Probably should have pressed the gas pedal but I'm stupid. So as I'm pulling out the whine starts up again, it being at about the same loudness as I had with my old monster cables. So I spent the next couple hours looking for a better ground spot, no love. One of the guys at the shop also told me to run a wire from my HU ground to the amp ground and from the yellow wire on the deck to the power on the amp. I did that and I got a lot of static and then I blew a fuse and I decided not to press my luck anymore by playing with the ground/power while the amp was still getting power. I didn't get a chance to run my ground to my amp ground though so I'll probably try that tomorrow or the day after christmas to see if I can figure out what's going on. So really, in the last 2 days I've spent several hours and $30 to get the alt whine to sound like it did before I started screwing with it //content.invisioncic.com/y282845/emoticons/wow.gif.23d729408e9177caa2a0ed6a2ba6588e.gif Thanks for the suggestions though and I'll let you know if I ever find out what it is.

 

[jer_stud56 10+ year member]

One reason why home audio wins over car audio. Ground loops. G'luck man.

- pe@ce

 

[Super98 10+ year member]

I ran the power & ground from the HU to the amps in the back, and my static and whine went away a little bit, but not completely. I had the noise down almost all the way, then added a second amp and satellite radio, and the noise is back. I put in ground isolators next to the HU, but I've found they have to be in the right spot facing the right way, and if they get bumped or nudged, the noise comes back in so I put them away.

I've come to the conclusion that certain HU/amp combinations are destined to make noise together. It's gotta be. The next thing I'm gonna do is put a capacitor on the alternator output wire. That should at help or maybe get rid of the whine.

 

[turbo328 10+ year member]

I just did an install last week that had a bad problem with road noise. My problem was that my rcas were too close too my power wire. I've always been told that your rcas should be at least 18 inches from your power wire. They also shouldn't cross the power wire at any point.

 

[southprk 10+ year member]

I didn't have any alternator whine problems, but I have a set of RCA's with a ground wire on them .. seems like it can't hurt?

 

[Shugarra 10+ year member]

I didn't have any alternator whine problems, but I have a set of RCA's with a ground wire on them .. seems like it can't hurt?

If I'm thinking of the right thing I do believe that is supposed to be used for the remote turn on, however, using it as a ground might not be a bad idea at all! I'll give that a shot tomorrow, thank you!

Mike

 

[ShakinSupra 10+ year member]

I've hear the remote on RCAs is actually for a ground, to connect the shield of the amp to shield of the HU.

Anyways, I had the same problem. Try disconnecting the RCAs from your deck and output from something else with

RCA outs to see if the noise is still there. If not you know the noise is coming from someplace past the HU. My noise was coming from the HU. I re-grounded all of my components, and tried a ground isolator, but the noise remained until I replaced my crappy Panasonic HU with my Nakamichi... Gone! I installed the Panasonic into another car not to long ago... and the alternator whine returns...

It should pretty much always be able to be resolved -without- replacing equipment though...

 

[southprk 10+ year member]

Hehe, no problem .. It actually was a ground.. It came in an amp kit that included a remote wire as well. I didn't end up using it since it was my first ever install and I was stumped. Also running a remote along the rca's might not have an effect, but any current along a line level signal I'd skip.

 

[Shugarra 10+ year member]

I finally got it to work!

Well, I think I said earlier in the post that I had tried to run a wire from the constant power on the deck (yellow wire) to the power on the amp and another wire from the deck ground to the amp ground. Well it didn't work the first time, but that was just trying to touch the wires to the terminals. Today I decided I'd do it right and actually screw the wires in and that's what did it. The alt whine is COMPLETELY gone! I'm so happy! Thanks for all the help you guys have given me. I'm off to listen to some music sans alt whine.

Mike