Where am I getting all this noise from?

[JoeFaSHO4]

I installed an aftermarket amp in my car for two 12" - Setup is: RCA outs to the aftermarket amp. I had to "shair" the wireing harness that goes to all 4 speakers and factory amp+sub. I "shair" the remote out wire by hooking both the harness and the aftermarket Remote line togeather.

Every thing sounds fine with the ACC turned on. But when I start my car the speakers have a background wine in them. eaisly heard, it runs up and down with the RPMs of the car. Guessing, seems to me somthing like the alternator, or other eletronic, is drowning noise into the frame.

Is there any thing I can do to clean out this noise?

 

[93medusa]

Alternator whine is the technical term for what you are experiencing. It is a pain in the posterior to track down what is causing it. The place to start is with your grounds, make sure that your amp and your head unit are both grounded to bare metal and secured tightly. Then, make sure that your RCA cords are not crossing over or running with any large power wires.

If this doesn't work, you may need a filter of some sort. there is more information here:

http://www.crutchfieldadvisor.com/S-OKU7Bit9XcF/learningcenter/car/noise.html

 

[LOUDSHO92]

I took care of my wine with a capacitator. It worked out quite well as stopped the lights from dimming. Some think that it is just a quick fix but well it works and served its purpose. Also it allowed the subs to hit harder.

 

[UnsungZero]

a cap would fix this

 

[SHOMA]

Are your RCAs and power source running on the same side of the car?
Kevin

 

[Camarok]

if push comes to shove get one of these things

 

[krupt89]

Are your RCAs and power source running on the same side of the car?
Kevin

Ditto.....and what brand of wires are you using?

 

[93medusa]

the brand of wires is of no consequence to his alternator whine. It has to do with how they are installed.

 

[krupt89]

the brand of wires is of no consequence to his alternator whine. It has to do with how they are installed.

I have seen it happen to a few of my friends using very cheap unshielded RCA's. Even w/ power and RCA running on opposite sides of the car they acted almost like an antenna picking up ALT wine and other noise before it reached the amp(which in turn those noises were amplified as well). Just my 2 cents but i would invest in a good set of shielded RCA's and make sure your power and RCA's are running on seperate sides of the car. Should get rid of the ALT wine

 

[93medusa]

Shielded RCAs are a marketing scam. At least, that is how I feel about them. I spoke directly with an Alpine rep that was demo-ing alpine gear at a sound off. He had two pieces of 18 guage wire twisted together with a high quality RCA connector soldered on to it. I was like "don't you get noise like that" and he proceeded to tell me all about how High end RCA cables are a scam. I tend to agree with him. I've been using very inexpensive RCA cables and have never run into a noise problem. I don't think i'd go as extreme as to simply twist two wires together, but you get the point. Of course, preamp voltage plays a very large role in noise rejection. every head unit I have ever run has had at least 4 volts of output. So perhaps if your head unit is an older piece that only puts out say 1 volt, you might have more of a problem than I did. I'm just relaying my experience. But I wouldn't go buying new stuff until i confirmed that the old stuff was the problem.

 

[krupt89]

Shielded RCAs are a marketing scam. At least, that is how I feel about them. I spoke directly with an Alpine rep that was demo-ing alpine gear at a sound off. He had two pieces of 18 guage wire twisted together with a high quality RCA connector soldered on to it. I was like "don't you get noise like that" and he proceeded to tell me all about how High end RCA cables are a scam. I tend to agree with him. I've been using very inexpensive RCA cables and have never run into a noise problem. I don't think i'd go as extreme as to simply twist two wires together, but you get the point. Of course, preamp voltage plays a very large role in noise rejection. every head unit I have ever run has had at least 4 volts of output. So perhaps if your head unit is an older piece that only puts out say 1 volt, you might have more of a problem than I did. I'm just relaying my experience. But I wouldn't go buying new stuff until i confirmed that the old stuff was the problem.

I agree on not buying anything untill everything else is checked but thats were i would start if everything else was ok

 

[JoeFaSHO4]

At first I had the RCA and power running down the same side, I then fixed that by moving the RCA to the other side. Still the same noise. Wine w\ the RPM

If this helps anyone- I connected then NEG wire to the NEG termanal on the battery and still could hear the alternator noise.

wtf

Im using rockferd fosgate RCA lines and Im not sure but i believe 16 gage power line. To a 300W amp

 

[LOUDSHO92]

I would recomend going to an 8guage wire at least for the amp. 16guage is nothing and wont allow the amp to draw the power it needs.

 

[AutoSHO]

16 gauge is Tiny!

For a 300w amp I would run 8 gauge as a minimum, maybe 6 gauge. Also, check to see that the noise filter on your coil pack is plugged in.

 

[JoeFaSHO4]

For a 300w amp I would run 8 gauge as a minimum, maybe 6 gauge. Also, check to see that the noise filter on your coil pack is plugged in.

Coil pack noise filter?

 

[JoeFaSHO4]

I would recomend going to an 8guage wire at least for the amp. 16guage is nothing and wont allow the amp to draw the power it needs.

Im actually not sure what gage it is. i could be 8 because its not too small. it beats like its supposed to. im not haveing a problem with that. just the noise.
the wire is about the size of a pen, maybe a little smaller.

 

[LOUDSHO92]

Well the amp kit should tell you what guage it is as well as it should be on the wire. If you have 8guage then get a capacitator, it will help things out.

 

[element913]

You have a ground loop isolation problem, a cap may in some cases fix this problem but i would try rerouting your RCA's AWAY from the fuel pump first. Instead of making sure your grounds are all grounded to metal, ground the amp and headunit at the same place (preferably at the engine). Noise filters work but will hurt your overall sound quality. As far as wire gauges go, changing the gauge of wire will not effect sound quality or interference (it will however lessen your chances of burning up a wire). A test you can try is to turn the car on and see if when you change the gains on the amp if the interference becomes amplified with the music, if it stays the same then you have a ground loop problem, if it gets louder or quieter with the gain then you have an rca relocation problem. As far as RCA's go, I did at one point use cheap rca's, and although I had no interference problems, when i upgraded to Monster Cable Micro XLN RCA's, i noticed my speakers had alot more midbass. If high quality RCA's were a scam then people wouldnt buy them, and that tells you how much Alpine guys know i guess. Another thing to note is that in a demo place at a store (not in a car) there is alot less interference and its stable, it doesnt fluctuate like rpm so its harder to recognize. High quality rcas are not necessary. As far as Twisted pair RCA's, they dont do what they say as far as cutting all noise (only certain frequencies). Fosgate has a set of RCA's with a ground loop isolation wire, that you ground do the car to eliminate interference, you might want to try these. If you run a ground wire from the amp directly to the battery (or engine block) you can eliminate the interference that way, and increase the amount of voltage your amp sees.

Hope it helps,

 

[MelectroK]

(4 years professional car stereo installer talking here)

What size fuze came factory in your new amp?

The quality of the RCA's do not matter even if the wires are ran on the same side. Cheaper RCA's will pick up sounds of this type much easier though. However, these sounds should not exist in the first place.

Check all your grounds, on the amp and the radio, and processor if you have one. Make sure they are tightly bolted to some metal on your chasis somewhere. But make sure you use a wire brush or a file to remove all paint from between the sheet metal you connect to and your ground cable. Also do not trust factory radio grounds.

Second remove your alternator and clean its grounding points to your engine with a wire brush or a file. Then make sure you get the bolts nice and tight. Also, do the same to your ground cable from your engine to your chasis, and once again to your battery post and battery ground to chasis.

If the sound is still present, make sure your alternator is the problem. Disconnect the wires from the alternator, start the car and try it. Dont run like this to long though you will be running off your battery. If the sound goes away, which it normally does, your alternator is the culprite. Replace the alternator, or regulator. A simple thing to try first is placing a small capicitor directly to the alternator output to the alternator frame. The guys at radio shack should be able to help you find one.

Always attack a problem at the source. Dont filter every component there after. If you hear alternator noise in the sterio, it is also throughout the rest of the car. ECM, PCM, EEC, ect. ect. In bad cases can hinder performance.

 

[JoeFaSHO4]

I Think that my Alternator is on its way out. I hear a ticking noise that is becoming rather loud. but im actually not very sure what it is thats ticking. it stays consistant and does not change with the RPMs. anyone have a good idea of what it might be? Maybe if i buy a new one it will solve the noise problem too?