Printer Friendly Forum Posts - unusual whining noise

My origional system was blown when a ground was shorted out. I replaced the origional amp (65x4 RMS Pioneer) that had blow, with a new one (Kicker 120x4)in the smae location. I am now getting terrible noises. I have tried many things and put hours into this instillation. The power cable is ran down the drivers side, and the remote/speaker wires are on the passengers side, amp under passenger seat. When i heard the noises, I thought possibly the head unit was blow, so i replaced that as well, the noise continued, only when the engine is on of course. In trouble shooting, i ran speaker wires directly to the amp, and it cut out some noise, but not all. Then i pulled all of the rca cables out of the car, and replaced them with standard speaker wires. This made the noise go away a little more, but it is still there. I have connected a battery opperated mp3 player directly to the amp, and it plays clearly, so i know the amp is working properly. I have also tried running cables from the stereo directly back to the battery, bypassing the harness, and still nothing. I have no computer in my car, and it is a 93 full size 2 door chevrolet blazer. I am just not sure what else can be done.

Read the grounding sticky posts. You need to improve the ground connections on both your amp and your head unit. And if your HU is a Pioneer, you may need to replace it with a different brand.

BTW, what do you mean by "a ground was shorted out" and you "blew" your amp? What exactly happened?

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I have 2 amps in the truck, the first is to power the speakers (2 6x9 eclipse 4 ways, 2 boston acoustics 4x6 2 ways, and 2 sony xplode 6in.) I have another mono channel amp bazooka owering 2 bazooka 12s. I tightening a speaker wire on the bazooka amp, and it touched the ground coming from the seat. It then shut the entire truck down, and my 4 channel amp, which i was not even touching blew, or stopped functioning ( it would come on, and just make a loud clicking noise about every 2 seconds. The head unit also blew, so i replaced them both. New amp, a kicker as mentioned, new head unit was a pioneer 4x50 watt. Thats how everthing started. I have done a lot to ensure that the ground is perfect. I added a 4 gauge wire directly to the amp from the battery as troubleshooting. THis made no difference, so i used that 4 gauge wire directly to the headunit, still nothing. I also tried this using the positive charge to both the amp and the hu, and still nothing. I dont know what else to do. Is there anything else i should try?Thanks.

As DYohn said, try a different BRAND of head. Pioneers are NOTORIOUS for noisy, crappy ground planes within their head units. I bet that if you find a different brand of head, your noise will go away immediately.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

Could this really make enough difference for the sound to be unclear, or are yall just bias against pioneer brand. I admit its not my favorite, but i would perfer not to purchase an entire new head unit if that it not the actual problem. I have had good experience with my pioneer headunits in the past, I want to fix the problem, not cover it up. If pioneer is really that bad, i am willing to replace it.

I'm not biased against any brand. I just know that Pioneer has quality issues with the ground planes in their heads and it exhibits as uncontrollable alternator whine. Simple as that.

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Okay, today, i ran wires directly from the battery to the head unit, both positive and negative, Did nothing. I also tried going rca cables, across seats to amp, still nothing. I know the amp is cable of playing clear music, i used the mp3 player. I am completly leaning towards ground loop. You all say that its the brand head unit, which i believe could be true. I am jsut suspicious, because i have had 2 pioneer head units in the past, which niether had any trouble with noise. Do i need to run a ground cable directly to the amp. The amp is powered with 8 gauge wire now. The rear amp is grounded to the rear seat bolt.

rjp9602@cox.net wrote:

The rear amp is grounded to the rear seat bolt.

This is not generally a good location as seat bolts are made from hardened steel and often screwed into nuts that are welded to the unibody. Have you measured your ground return resistance? If it's greater than an ohm it is a bad ground.

I still think you have a defective head unit. This issue effects probably 25% of all Pioneer heads. It is very common. Connect a ground wire to the outter ring of the RCA cable and see what happens. If the noise changes, it's a defective head unit (or a very poor ground connection).

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Okay, i will try that, what if i am not using rca cables, does that still apply. I have the truck wired through speaker wires that are spliced into the harness. I am running the rca cables as test over the seats. Should i ground out all of the rca cable sheildings, or just one of them, and also do i need to do it nearest the hu or amp. I have tried 4 different pioneer headunits, and they have all made the same sound.

What do you mean you are using speaker wires spliced into the harness? How are you connecting the head unit to the amps?

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When I use RCA cables, the whine seams to be louder. I cut the factory harness off. Typically a harness kit would convert the factory harness to what is needed for the specific head unit. From the wiring kit coming from the Head unit, I use the speaker outs, and go to the amp, then the speaker outs on the amp goes back to the dash, which is where all of the speaker wires originate and go out to the speakers. So it goes out of the head unit through the speaker outs, spliced into speaker wire, which carries it to the amp, then through the amp back up to the dash, which then is spliced back into the factory wiring for the speakers. All of the factory speaker wiring is used, just with an amp in-between the head unit and the factory wiring harness. Does this make since, I am having trouble explain it.

Roland Prestenback

OK, so you are using the high-level inputs on your amps? Generally this makes for much worse noise issues and much lower quality sound than using the line-level (RCA) outputs from the head unit to the RCA inputs on the amps. If this arrangement caused MORE noise, then either you have major ground issues, completely defective head unit or your amplifier gain is cranked to max. Is your gain cranked?

I the first thing you need to do is measure your ground return resistance and improve your grounds for the amps AND for the head unit if any of them read one ohm or greater. Do you have access to an ohm-meter? Then I highly recommend using proper RCA cables from your HU to your amps, and make sure your gain is properly set. If you do these things and still have noise, then you have a defective head unit OR a major issue with the car's electrical system.

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As much as I really do not want to say this, I am thinking that I have a major issue with the cars electrical system, after the shorting that happened that I mentioned above. I don’t have a clue what this will involve, but I have done almost everything else possible. I have grounded the amp and the head unit directly to the battery, this is also the 4th head unit I have tried (all pioneer) with this configuration. I don’t think that I am having an issue with grounds. The gains are turned all of the way down, but there is still a small whine. I would also prefer not to have to have the gains all of the way down, this means I am not getting the full performance out of the amp. The weird thing is that I was able to get the mp3 player to play crystal clear. The head unit will also play clearly when bypassing the amp. I will check the ohms tomorrow, I have a multimeter.

rjp9602@cox.net wrote:

The gains are turned all of the way down, but there is still a small whine. I would also prefer not to have to have the gains all of the way down, this means I am not getting the full performance out of the amp.

That is ABSOLUTELY not true. If your head unit can output enough voltage, then the amp will be driven to full output, no matter WHERE the gain is set.

What is the output voltage of the head unit, and what is the acceptable input voltage on the amplifier? If those overlap at all, then the amp can make full output. End of story.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

I didn't read all of the responses to your post so if someone else covered this please forgive me for reposting it.

You need an ohm meter to do this. Unhook the patch cords and speaker wires from your amp. With the ohm meter put 1 lead on the shield of your amp's RCA inputs and the other lead on any 1 of the 4 non-bridged speaker wires. do this with each of your 4 RCA's if you get anything more than 10 ohms, there is a problem with your amplifier. It is an easy fix so let me know what you find.

[QUOTE=rjp9602@cox.net]I have grounded the amp and the head unit directly to the battery,QUOTE]

If you have these directly to the battery (physically connected). Disconnect them, and ground your HU and amp to a clean piece of metal (no paint bare metal) on the vehicles chasis. An easy example may be where your seats are bolted to the floor. or the steel frame inside your dash.

do you have real good quality RCA's? thats a possible problem

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Oh Man Theres Troy

Alright, let me see if i can answer these. For the grounding of the amp, i have it grounded to the bolt of the seat, I have ran a 4 gauge wire directly to the battery as a test, nothing. I have had the headunit grounded to the metal frame, as a trial, i ran a wire to the battery. Neither made a difference. I have fairly decent rca cables i guess. They came with the wiring kit. I am still a little confused about how to check the ohms as mentioned with the ohm meter and such.

My particular head unit puts out 50x4 watts max i suppose. it also has 6 rca outs.

you mean 3 rca out puts? they are in pairs left/right. Not to hurt feelings here but IMO you should take this vehicle to a professional and have the stereo system re-wired. I have read these posts and it seems to me your are like a dog chasing his tail. Before you kill anymore amps or cd players I would spend the money and have someone that does car audio for a living figure it out.

xtremej wrote:

you mean 3 rca out puts? they are in pairs left/right. Not to hurt feelings here but IMO you should take this vehicle to a professional and have the stereo system re-wired. I have read these posts and it seems to me your are like a dog chasing his tail. Before you kill anymore amps or cd players I would spend the money and have someone that does car audio for a living figure it out.

I agree. Time for help.

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I did quite understand, you shorted a speaker wire to ground and the truck shut off?

There would have been some serious sparks flying to do that. Suggest you set your multi meter to ac and check voltage at the amp with truck running. If you find about 36 v ac you blew a diode out of the alternator, just bad enough for the amp to pick it up.

Alright, i have an update on the issue. Yesterday, i connected the power and ground and the acc cables to another vechicle, and it still made the whining noise, except it made the noises from the other vehicle. Does this mean anything. Today i am going to go and buy a different brand head unit, what do you all reccomend as the best for noise elimination>?

Like I said, you need to take your car to a shop and have the electrical system checked out to make sure there is no damage before you proceed. Please.

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Could you just tell me what brand is the best for noise, i really cannot afford to bring it to an electronics store and have it done, that will cost upwards from 200 bucks.

Eclipse. And please also install your system properly: improve your amp grounds, don't use seat bolts. Drill a proper ground connection (read the grounding stickies.) Use RCA cables not high-level speaker inputs. Set your gain properly. Make sure nothing can possibly ground out. And when the noise is still there with your new head unit, take the car to a shop and get it fixed.

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Eclipse seams to be a little out of my range, i would have to get the cheapest one, and it doesnt have aux inputs or a remote. Is there a nother choise, possibly alpine? There is a nearbye alpine dealer.

rjp9602@cox.net wrote:

Eclipse seams to be a little out of my range, i would have to get the cheapest one, and it doesnt have aux inputs or a remote. Is there a nother choise, possibly alpine? There is a nearbye alpine dealer.

you could buy the best head unit on the market and it will not fix your installation issues. how is it that you are willing to buy a new head unit, but you wont spend money to have a professional troubleshoot and fix the installation?

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Spend the 200 bucks, if you fry a $200 cd player because your wiring is hideous I guarnatee that the shop that sells it will void your warranty. Trust me I see this all the time when folks are trying to save a few bucks and it ends up costing them more than just getting it done by a audio installer to begin with. Pioneer is the only one to avoid currently out of the better name brands. If your looking for something affodable that sounds decent, look into kenwood, jvc, clarion, and am sure others can add to this list.

Tape the RCA jacks. Easiest and less time consuming.

They might be touching. I work at BestBuy car audio. Some Kid from Verizon ask "my system is making a whining noise?" All I remember he has 2 alpine Type-R.

I told him the electromagnetic field (EMF) spiel could carry thru RCA if any power(even the cars harness can produces EMF) and rca are ran together. Then I told him about bad ground. I told him first tape the RCA jack. Even if they are not touching you still got EMF.

What happened? Two weeks later, saw him at work, no more noise. Electrical tape around all the RCA jacks. He was happy.

If you get a new deck grab one with 4volt pre-out like some Kenwoods. They create less distortion.

electrical tape blocks electromagnetic interference? posted_image

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jjermzz wrote:

Tape the RCA jacks. Easiest and less time consuming.
They might be touching. I work at BestBuy car audio. Some Kid from Verizon ask "my system is making a whining noise?" All I remember he has 2 alpine Type-R.
I told him the electromagnetic field (EMF) spiel could carry thru RCA if any power(even the cars harness can produces EMF) and rca are ran together. Then I told him about bad ground. I told him first tape the RCA jack. Even if they are not touching you still got EMF.
What happened? Two weeks later, saw him at work, no more noise. Electrical tape around all the RCA jacks. He was happy.

This is absolute BS. If tape helped then it was because the connections were loose. Tape will have NO, ZERO, NADA effect on EMI. Please do not spread bad information here, thanks.

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DYohn] wrote:

QUOTE=jjermzz]Tape the RCA jacks. Easiest and less time consuming.
They might be touching. I work at BestBuy car audio. Some Kid from Verizon ask "my system is making a whining noise?" All I remember he has 2 alpine Type-R.
I told him the electromagnetic field (EMF) spiel could carry thru RCA if any power(even the cars harness can produces EMF) and rca are ran together. Then I told him about bad ground. I told him first tape the RCA jack. Even if they are not touching you still got EMF.
What happened? Two weeks later, saw him at work, no more noise. Electrical tape around all the RCA jacks. He was happy.

This is absolute BS. If tape helped then it was because the connections were loose. Tape will have NO, ZERO, NADA effect on EMI. Please do not spread bad information here, thanks.

[/QUOTE]

aww, i wanted some of his magic tape posted_image

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Okay i fixed the problem i believe, i went with a pioneer head unit that uses high level outputs instead of the low level outputs, and it sounds great. Gain can be set all of the way up with no noise problems. I guess im good at wiring after all.

rjp9602@cox.net wrote:

Okay i fixed the problem i believe, i went with a pioneer head unit that uses high level outputs instead of the low level outputs, and it sounds great. Gain can be set all of the way up with no noise problems. I guess im good at wiring after all.

you did turn the gains back down to a proper setting after you tested for noise right? with a high preout voltage head unit, setting the gains all the way up would be a bad idea.

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Of course, just as a test for noise, did it turn them up. Thank all of you for your help.

DYohn] wrote:

QUOTE=jjermzz]Tape the RCA jacks. Easiest and less time consuming.
They might be touching. I work at BestBuy car audio. Some Kid from Verizon ask "my system is making a whining noise?" All I remember he has 2 alpine Type-R.
I told him the electromagnetic field (EMF) spiel could carry thru RCA if any power(even the cars harness can produces EMF) and rca are ran together. Then I told him about bad ground. I told him first tape the RCA jack. Even if they are not touching you still got EMF.
What happened? Two weeks later, saw him at work, no more noise. Electrical tape around all the RCA jacks. He was happy.

This is absolute BS. If tape helped then it was because the connections were loose. Tape will have NO, ZERO, NADA effect on EMI. Please do not spread bad information here, thanks.

[/QUOTE]

I'm not saying I saw a ghost. Its a true story. In his case, the JACKS WERE TOUCHING, when he put electrical tape it created a gap(so they don't touch any more).

I never said Electrical tape will block EMF. I told the kid about EMF. Thats it.

It was the easiest solution ever and it was free. No new radio solved the problem. Electrical tape.

If someone told you to try it and it didn't work would you be mad? How bout if it worked? How much is really invested in trying this. It is worth try. In my case it worked

If RCA jacks are shorting out to each other then either the RCA cables are crap or the gear is defective. No commercially available stereo RCA set will allow jacks to short out to each other without a lot of effort and damage. And if you mean the plastic insulation was touching, then adding tape would still do nothing. Perhaps you solved this particular problem when you added the tape, but unless the metal parts were touching (and if they were you have bigger problems) it was not the tape that solved it, it was coincidence. It is physically impossible for electrical tape to block induction.

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