Rep Power: 296

ok, so i go in and install my us amps usa 150 to run my vifa custom crossover'd components, and it has a little bit of alternator whine, but only if im really revvin it, is there any simple fix to cut it down or get rid of it all together? i can provide you guys with any answers that you need to the questions you are going to have to ask to diagnose the problem, thanks in advance -alex

 
Rep Power: 0

all u have is a 150watt amp and a pair of crossovers, rite?.....in a 7th gen civic?.....if so its the ground....almost 100%......if u have more stuff (ie 2k watt amp) then ure sol

 
Rep Power: 0

also, if your headunit is aftermarket, reground that bitch... stock ground sucks

 
Rep Power: 296

ok, so what do i do with the ground, like clean it up?, make it shorter? its on pretty securely, should it be located away from other things? like the rca's? thanks - alex

 
Rep Power: 0

It's the RCA cables. I had the same problem and had tweeter reground everything. There was still alternator-influenced noise. I have 2 pairs of RCA cables to my 4ch amp. One pair is a Monster Cable car audio RCA set and another is a Monster Cable home audio RCA set. Needless to say, the home audio cables are much better insulated. After switching the cables into each output, the Tweeter install guy and I determined that it was one faulty set of RCAs. So try hooking up a set of nicely shielded home RCAs or try rewiring so that it avoids any possible sources of interference.

 
Rep Power: 323

Vifa - you could try installing a ground loop isolator between your deck and the amp on the RCA's for your front speakers. I don't know your AMP brand as far as quality, but I'm using a 4 channel PowerAcoustik that I think is likely the culprit - lower price amps don't seem to do as good of a job filtering noise. When it dies I'm upgrading to Alpine....

 
Rep Power: 0

Ground loop isolators are a quick fix that would probably eliminate your problem. But I've been told they are more of a band-aid and not really the best fix unless you absolutely have to. You just probably need to run your RCA's better. Make sure the cables aren't looped up on top of eachother. Also, I ran the cables under my carpet on the drivers side, over to the center console and then up to the headunit. If you're not using an aftermarket headunit it could be your Line Output Converters (if you're using them) I have had those be the ultimate source of my noise problems before. Check the ground, sand any paint off that is around where the ground is and make sure its to a solid part metal part of the car's chasis. Good luck!

 
Rep Power: 323

Dups - I agree it's a band-aid but it does work. With my install last summer (2k1 coupe) I ran RCA's down the driver's side, power & remote down the passenger side. All components were grounded at a single point through a distribution block, and I still had alternator whine. My guess is that it's the AMP, but I can't be certain until I actually replace it.

 
Rep Power: 329

ground the HU to the same screw as the cigarette lighter piece if you want. thats a fairly short wire and easy to get too, no sanding needed either.

 
Rep Power: 296

ok, im going to reground the head unit and upgrade my rca's ( blue stinger ones from like 2 years ago) the amp is a good quality one so no worries there, and its groundd is fine too, but the whining does get louder with the ac fan on high ( hmmm.....), oh well, anything else?

 
Rep Power: 812

Get a ground wire kit for your car (under hood). Check out the thread called DIY: Ground Kit. It will help with grounding issues and may improve stereo performance.

 
Rep Power: 329

ac=big load on alternator=more whine. mine is quiet now except when ac and headlights are on, i haven't conquered that beast yet.

 
Rep Power: 0

alternator whine is a strange beast...
I've done installs on a LOT of cars, and i never really did any extra work to NOT get alternator whine, but for some reason, I've never had to dea with alternator whine...
even with some of my GHETTO first installs

 
Rep Power: 323

Ground loop isolators are the only thing I've found to kill it.

 
Rep Power: 296

ludlam, i feel ya on that, i did a ghetto *** install ( like my 2nd one ever) and no alternator whine, but then i do mine and i get it!!! ahhh, oh well im gonna try some of the things listed above and then ill report back, thanks for the help all!! -alex

 
Rep Power: 0

I know professional installers that hate working on our cars because there is just a lot of noise to be picked up from our civics. Anyways, almost all of my noise was in the center console where the radio and A/C controls are. I just had to keep moving the wires around and I finally got rid of every last bit of it. Just play with it and you can make it work hopefully without having to resort to the ground loop isolators. That was going to be my first thing to do to eliminate my noise and now I'm glad I did it right. Good luck!

 
Rep Power: 323

Dups - there's not that much room to move stuff in the console - what exactly did you move (and to where?) that made a difference.

For the real pros here - what are negatives of using ground loop isolators?

 
Rep Power: 296

I know that the ground loop[ isolators add a hell of a lot of resistance to the ground line, which means that the amperage flow from the batt to the amp and the amp to the batt is impeded a lot, which affects the overall output of the amp.

 
Rep Power: 346

I had the same problem for the longest time...I pinpointed the source of my whine to right behind my deck, and i got rid of it by jiggling the RCAs around behind the deck...but if I didn't have the wires in exactly the right spot, the noise would come back. So if I broke to hard or made a hard turn the whine would come back sometimes...I just gave up and went with the RadiosShack ground-loop isolators. i spent so much time on it and nothing held the wires in the perfect spot because the wire would generally move as soon as I inserted the HU. I don't really know what the negative effects of the isolator is...but i guess ignorance is bliss.

 
Rep Power: 323

how does using a cap affect this? To make sure I have the item defined right - the ground loop isolator is a little round "thing" with two sets of RCA female connections (1 on each side).

 
Rep Power: 329

cap really won't do much except provide something to keep signal cables away from, that and it needs to be grounded just causing another ground loop problem unless you have it well grounded and/or use a dist. block.

 
Rep Power: 0

As far as moving the cables around in the console, I just did basically what fonto described. All of my noise was behind the deck and going down to the floor. I pulled my cables under the carpet and pulled it a little closer towards the transmission and then ran it back and up. Which helped a little. Then for behind the deck I just jiggled wires around till the noise went away and then tried to find places to zip tie the wires to keep them from moving and bringing the sound back. I've been fine since then and I have a tendancy to take turns hard from time to time... so I'm sure my way worked

Then about the ground loop isolators.... what I've been told is exactly what auto84 said as well as the fact that it also cuts out frequencies to eliminate the noise. Which while you may or may not miss those freq. it still is considered a band-aid for that reason. It is better to remove the sound properly than to use those. But if you're not going to competition and/or you just don't care then I suppose it wouldn't really matter. This is just what I've always been told.

 
Rep Power: 0

To throw something else into the mix, I still have alternator whine even with upgraded RCAs, but the main problem is an ignition pop? I don't know what to call it, but my Tweeter install guy says the interference pattern sounds like it has something to do with the ignition, in addition to the alternator whine. I have to turn the gain on my rear 2 channels WAY down, which really sucks because my Infinity 605cs fronts don't give much bass (no subs yet). Any ideas on the ignition noise?

 
Rep Power: 346

I would maybe try checkin your grounds...this would be the first step.

 
Rep Power: 0

I have really good RCAs for my fronts and I still had engine noise as well. You just have to find the perfect place to run the cables where they don't get interference.

About the ignition pop.... I don't know for sure, but isn't that a result of your radio just turning on when the car does? I don't know for sure but I think when I used to run my amps with my stock headunit I had that problem but then I got my new headunit and ran my remote wire to the headunit instead of the fuse box. So when I started the car before the amps came on at the same time causing the popping sound. But now that I have it going to the headunit there is a delay before the amps turn on so its all good. I might be way off on this though, so somebody correct me if I'm wrong. The ignition pop shouldn't hurt anything though I think. But I don't know for sure.

 
Rep Power: 346

I took my ground-loop isolators to see if my car was making any noise...and it wasn't making to much, so I prolly leave them off. I notice a lil more staticy hiss, but it could have been because my carport was dead quite. If I turn my HU up to 2 on the volume I could not hear the hiss anymore (although, this could be phsyco acoustics, but I felt like the hiss was Slightly raising in volume when I reved the engine...but whatever)...I am going to try this for a few days and see if my wires move around and if a noise comes around. I'll leave the ISOs in the car just in case.