Buzzing noise

[rayray086]

So I recently fitted an amp and aftermarket headunit to my sister's Polo. It works very well and sounds much better than the stock setup. However, whenever she drives the car, there's a buzzing sound and it seems to go in-sync with the revs, i.e. the higher the car revs, the more audible the buzzing sound becomes. Also, starting the car with the headunit on also gives a bit of trouble, as if the car is slightly struggling. However, there are no cut-outs or any other trouble.

I used a standard wiring kit to hook up the amp. I'm not quite sure but the power/ground cables provided were either 4ga or 8ga. Ground cable for the amp is about 40cm long. The headunit was adapted to the stock harness so I'm using the same wires that powered the old headunit. Same with the ground.

I think my problem is that the stock positive cables going from the battery to the starter/alternator are not rated high/thick enough. I didn't have this problem with my car as I upgraded all cables to 2ga/4ga when I did my installation. What do you guys think?

[RhysQ]

the buzzing noise generally means the power is not grounding properly so you'll have to check the wiring again. with old cars, using the stock thin wiring means it will not ground properly so you will have to go a lower power and earth gauge FROM THE BATTERY... 8ga should be ok.

[KI11Z]

i had this quite some time ago and was basicly told that your amp has a dodgey grounding point, just try changing your earth cables location; Failing that, I believe you can buy little in-line noise filters thatd eliminate the static . . . hope it helps

[Jondarren]

Your stock wiring is causing the problem i think. If you wire in the head unit independently of the stock harness this should help.

Its likely the grounding so run a stand alone earth cable and power from the battery for best results. Or earth from the chassis somewhere.

Much better to go direct than to add in some noise filter to the mix.

Cheers

Jon

[The_Hawk]

Is it a Pioneer head unit by any chance?

Pioneer units have a habit of blowing the track fuse on the RCA lines which cause the same problem. (you will prob also get noise when you turn on the AC/heater fan)

[Soundofav6]

that would be the altenator noise, try to turn the Gain down in the amp.
If not try this http://www.mobileelectronics.com.au/forums/index.php?showtopic=42644

[rayray086]

Not a Pioneer, a Clarion. The same headunit was used in my car and had no problems.

In regards to running a ground cable from the headunit directly to the battery - I keep hearing that ground cables should be short. Would this be a problem? I'll also check the grounding point for the amp.

Thanks for the link to Louis, will try that if all else fails.

[jnrm3]

hey just wondering how you ran the wirring?

-if you ran the power cable next to the rca's or along the same side of the car this will cause a buzzing sound.

-if your rca's have a earthing cable down the middle make sure its earthed and not being used as the trigger cable.

-also if you have unplug the rca's from the back of the unit while the car has been on you may have blown the trace wire in the unit it self causing a buzzing sound.

cheers
steve

[rayray086]

-if you ran the power cable next to the rca's or along the same side of the car this will cause a buzzing sound.

-if your rca's have a earthing cable down the middle make sure its earthed and not being used as the trigger cable.

-also if you have unplug the rca's from the back of the unit while the car has been on you may have blown the trace wire in the unit it self causing a buzzing sound.

Steve,

Yes, the power cable is running next to the RCAs! My RCAs do have a thin wire running between them (but insulated separately)... I used that as the amp remote wire :duh: So what is that wire actually for?

I always had the headunit and car off when fiddling with the connections so I'm sure I didn't blow anything (past experience has led me to be more aware about electrical safety :duh:).

Damn, I thought I did everything right! Thanks for the help!

[Elwoods 2LGL]

Hey Guys

Try Jaycar they have what you need

As well as seperating the audio & power lines here are some inline noise filters that will help


Quote from the online catalogue

Car noise filters or hot line filters are used to reduce noise and interference entering your car stereo through the power lead. The car alternator is one of the most common sources of problems, and these essential devices can help to reduce this. Three sizes available depending on the power rating of the affected amplifier / radio etc.
This unit is effective against 'engine hum' and 'ticking' caused by alternators, ignition coils & spark plug leads in automotive car radio & stereo installations. Connects in series with the battery supply (hotline).

5 Amp
http://www.jaycar.com.au/productView.asp?ID=AA3072&CATID=&keywords=filter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=

20 Amp
http://www.jaycar.com.au/productView.asp?ID=AA3076&CATID=&keywords=filter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=

40 Amp
http://www.jaycar.com.au/productView.asp?ID=AA3081&CATID=&keywords=filter&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=