Noise grrrr, Sound system noise Options

[insec7]

Ok I got a weird problem that I cant crack. I hear this annoying noise out of my speakers wevery time the car is turned on, the pitch of the noise increases as I rev but it doesnt get louder.
Now I know improper ground causes this to happen, but I know I did ground my head unit properly so the other day I did a little test.


So I took out my head unit, and disconnected the ground from the chasis, but the head unit did not turn off, there was absolutely no change in sound/performance of it.
Then I started disconnecting other cables to figure out what grounding it. Finally when I unplugged the antenna cable, the headunit stopped working, this made me go WTF because it just doesnt make sense (to me anyway) So its obvious that the antenna is causing the noise because it serves as the ground.

Does anyone have any experience with this? Any tips/pointers would be greatly appreciated.

Thanks in advance.

[str8thugginit4ya]

Ok I got a weird problem that I cant crack. I hear this annoying noise out of my speakers wevery time the car is turned on, the pitch of the noise increases as I rev but it doesnt get louder.
Now I know improper ground causes this to happen, but I know I did ground my head unit properly so the other day I did a little test.


So I took out my head unit, and disconnected the ground from the chasis, but the head unit did not turn off, there was absolutely no change in sound/performance of it.
Then I started disconnecting other cables to figure out what grounding it. Finally when I unplugged the antenna cable, the headunit stopped working, this made me go WTF because it just doesnt make sense (to me anyway) So its obvious that the antenna is causing the noise because it serves as the ground.

Does anyone have any experience with this? Any tips/pointers would be greatly appreciated.

Thanks in advance.

Did you run your RCA cables, and your power wire right next to eachother??? When you run your power wire right next to the RCA cables, then the power wire generates noise distortion into your RCA's which come out of your speakers. Most of the time, it's either your ground, or what I just explained. So before you go checking your antenna, I would suggest you make sure you didn't run your RCA's and Power wire on the same side of the car. Seperate them, put one set of wires on the Drivers side, and the other set on the passengers side. If that is not your case, then I would suggest checking your AMP ground wires. More than likely, your amp ground wires are to be proven faulty than your deck's (I am not saying that as 100%, but read on). But usually aftermarket deck are run with the factory ground and antenna, so that probably wouldn't be your problem. For your amp ground, make sure you shaved off the paint around the bolt and body of the car where you are using your ground. You would want the ground touching PURE metal. Let me know if this helps.


-Ryan

[mgnt232]

Ok I got a weird problem that I cant crack. I hear this annoying noise out of my speakers wevery time the car is turned on, the pitch of the noise increases as I rev but it doesnt get louder.
Now I know improper ground causes this to happen, but I know I did ground my head unit properly so the other day I did a little test.


So I took out my head unit, and disconnected the ground from the chasis, but the head unit did not turn off, there was absolutely no change in sound/performance of it.
Then I started disconnecting other cables to figure out what grounding it. Finally when I unplugged the antenna cable, the headunit stopped working, this made me go WTF because it just doesnt make sense (to me anyway) So its obvious that the antenna is causing the noise because it serves as the ground.

Does anyone have any experience with this? Any tips/pointers would be greatly appreciated.

Thanks in advance.

With the noise getting higher as you rev, i would assume this is a condition called alternator Whine. I dont want to get too into details with it, but feel free to look it up.
Do you have a stock head unit? when you say antenna cable, do you mean the power antenna wire, or the actual larger antenna wire? It seems very odd that the antenna cable would serve as a ground (i know when i unhook my ground the stereo is down).

I don't know how much experience you have with audio systems, but i know the first time i did mine, i thought it was right, and i had messed up a few little things (wouldn't believe how little things can mess it up). Since then i have redone all the wires 20+ times, with new headunits, LEDS, underglows, switches, and have learned alot.

I would suggest just unhook your head unit completely, and take you time installing it again.

Also do you have an amp? and subs? everything the person before me explained is true (but im not sure if you even have a "system". When you run the power wires close to any signal wires (RCA) the power wires create a small electromagnetic field, that causes the "signal" to be distorted.
I hope some of that helps feel free to ask me any! questions, i have alot of knowledge about this.

[zonz540]

Ground loops suck. These guys are right about the RCA's being run in parallel with the power cable. DONT do it unless its for a sub, then you usually cant hear it anyway... If you still have issues, try a ground loop isolator. Theyre cheap and will quiet the sound, but wont get rid of it. Also, try grounding your antenna to the chassis with a larger cable and take off the paint to the spot you ground it. If it actually is your antenna, this should help. Otherwise, welcome to the world of alternator whine. Its a curse and can be a total pain to eliminate.

[brento_bot]

Firstly, what head unit are you using, because certain brands of head units have a poor ground plane. meaning the ground inside the unit is poor, so no matter how good the ground you have wired to the ground wire, it wil still produce the whine. A ground loop isolator is a band aid solution, it will not fix the problem it will disguise it. And you will loose sound quality.

I had terrible whine in my 4 amp system for ages, not being able to fix it. Until one day i read about the poor ground plane in Pioneer head units. So what i did was, I undid one of the screws in the back of the head unit, attached some wire to it, then attached the other end to the outer metal of the RCA wire plugged into the head unit, and alas sound gone. It worked for me, could work for you.

Hope this makes sense, hope it helps

[T3rrorbyte]

hope i'm not throwing the cat amongst the pigeons but i thought that the "running the positive feed next to the RCA's cause a whine" was a myth? Spent a lot of time reading talk audio forum the alternator whine is a common question and every time the positive/RCS thing is mentioned they say not.

Most faults are cured by one of the following

• Improving the grounding in the engine bay refered to as The BIG 3
• Making sure you have a good grounding spot for you amps i.e. paint sanded off, bolts connects to the chasis and not a panel
• The gauge of negative feed needs to be equal to the positive feed both from battery to chassis and from chassis to amps
• Finally running a direct negative feed from the battery to the head unit and running some bare copper wire round the RCS terminals


Hope this helps and doesn't offend

This post has been edited by T3rrorbyte: Aug 18, 2009 - 3:21 AM

[str8thugginit4ya]

hope i'm not throwing the cat amongst the pigeons but i thought that the "running the positive feed next to the RCA's cause a whine" was a myth? Spent a lot of time reading talk audio forum the alternator whine is a common question and every time the positive/RCS thing is mentioned they say not.

Most faults are cured by one of the following

• Improving the grounding in the engine bay refered to as The BIG 3
• Making sure you have a good grounding spot for you amps i.e. paint sanded off, bolts connects to the chasis and not a panel
• The gauge of negative feed needs to be equal to the positive feed both from battery to chassis and from chassis to amps
• Finally running a direct negative feed from the battery to the head unit and running some bare copper wire round the RCS terminals


Hope this helps and doesn't offend

Not to offend either, but I have had a LOT of experience with running the RCA next to your power wire and hearing distorted noise coming out of your speakers. I wouldn't say that I'm a master car audio guy, but I have hooked up a LOT of systems and I always avoid running those two wires next to eachother; and nearly everytime, I don't get those distorted sounds coming out of the RCA's. Many audio shops would ask you if you ran those two wires together FIRST, if you came to them with that problem because it's the most common one that creates that noise. Those bullets that T3rrorbyte listed are also very helpful if seperating the RCA and Power Wire doesn't work.

[brento_bot]

hope i'm not throwing the cat amongst the pigeons but i thought that the "running the positive feed next to the RCA's cause a whine" was a myth? Spent a lot of time reading talk audio forum the alternator whine is a common question and every time the positive/RCS thing is mentioned they say not.

Most faults are cured by one of the following

• Improving the grounding in the engine bay refered to as The BIG 3
• Making sure you have a good grounding spot for you amps i.e. paint sanded off, bolts connects to the chasis and not a panel
• The gauge of negative feed needs to be equal to the positive feed both from battery to chassis and from chassis to amps
• Finally running a direct negative feed from the battery to the head unit and running some bare copper wire round the RCS terminals


Hope this helps and doesn't offend

That picture is basically what i meant, except I only needed to run it around one, and i did it on the RCA lead.