Dear Sifu,

Recently have change my car audio player, but then i find out after change the have noise which is come from engine. How i test it ?

1) On the volume to 5, then start engine, heard sounds "~~ji....."
2) Then press petal, engine sounds louder, the "ji" sound will louder
3) I off the radio, start engine...dont have that "ji..."

Have any idea of this issue ? I try looking the shop person who install, they said memang will have bit sound d...
but previous player dont have this, so they maybe this watt is higher, so will have. Previous was 20W X 2 way, now was 62W X 4 way.

is that true ?

Bad grounding. Use thicker ground cable from amp to body.

1. usually bad grounding
2. usually using cheap cables will cause this. use better cables with filters.

Well not true... some cheap one like that unfortunately. If grounding like others suggested cannot solve, you can use noise suppressor on the +ve power supply. It is just heavy inductor and can be made by winding heavy enameled copper wire on toroid core.

Good luck

Thanks bro, i was using the cheap one as u said.

I can't get the means of the grounding u have mention, can briefly explain if possible.
The noise supressor is install on the power supply, means the car battery or what ?

If possibble to be done DIY ?

sorry bro, too many question...

You can try with thicker wire, ground at different point, use capacitor and etc. But if it is the player problem, can't do much unless you change it out.

power cable is near speaker wires...need to properly shield your speaker wires against power wires...this creates static noise that you hear... wire management is the key

grounding wire means Ve 12v- (negative) wire that come from the HU to the grounding (chasis) lor..
use bigger wire..but in case the connection use standard grounding that come from the car wiring,
its clearly that the HU is not good because standard wiring should be sufficient to rid the noise.
so, u have to put the suppressor.

supressor got 2 type, one of them are power noise suppressor and another is signal noise suprresor.
- power noise suppressor

this to be install on the power 12v+ positive wire from the power sources to the HU.
- signal noise suppressor

this one to be install in between HU RCA signal output to pre-amp/power amp.

This post has been edited by joefbi: Aug 13 2014, 04:05 PM

I presumed that you buy a set with standard mounting everything. You get it installed at a shop? Did you buy from that shop too? Then the shop probably don't have much technical knowledge. I think car audio accessory shops have this noise suppressor.

Normally the body of the radio is screwed to the car chassis. This is the grounding and this is also the -ve (negative) power supply. Only +ve (positive) wire goes to the radio and usually comes with the fuse. The good contact is important (thus called good grounding) to prevent this humming noise.

My old car last time I have the same problem with the radio (well cheap also ) Believed that the noise (like you heard, louder when you step on gas pedal) entered the radio through power supply line., I tried to put an inductor at the +12V power wire near the radio. It reduced a bit. Maybe the inductance wasn't enough. Since I had an unused transformer, I connected the secondary side to act like filter and the noise gone. Well this is not professional. You need to make sure the wire gauge can carry enough current for the radio to operate at full capacity.

The filter need to be installed as close to radio as possible. Probably just put behind the radio in dash cavity there. I don't know if you have any electronics knowledge but I suggest you ask someone who knows to brief. It is simple to understand. Maybe can ask other shop that know how to solve the problem, but they probably want you to replace the radio you had

This is good if you have separate amplifier too but I'm not sure in your case. Normally the cheap car stereo is just like the mini compo, give high power rating but actually it is not RMS rating. So quite meaningless. Therefore I presumed that the car audio is just 1 single unit.

yes, my car is only single unit of the car player, it dont have pre-amp.

So if need to cancel noise, mostly i will try DIY add the capacitor/compressor to reduce the noise.

Maybe need get the compressor and install myself.

I have ask others shop, they said cant do anything and ask me change whole car player. That the key you have mention.

thanks bro...

my car player was only single car player, which noise suppressor i should install ?
i believe the power noise supressor is suitable for my player.

Was wondering to cost of the power noise suppressor and installation fees on it.

If too expensive, maybe what can i do is ignore the noise until i get used to it.

no, the noise will anoy you the whole life. get rid of it..
get the power suppressor..i think it's cheap..will not cost you over 100 bucks + installation IINM

This post has been edited by joefbi: Aug 13 2014, 05:42 PM

u need BIG cable

Noise can be from several source. Maybe this article can give you something to work on. I would say power noise suppressor is not expensive. I guess should be less than RM50? I have no idea

http://www.crutchfield.com/S-vjpyGXYfAS0/l.../car/noise.html

thanks bro, my case is when off engine the sound is totally gone. Suspect will be the power supply, will try to install the power noise suppressor first. Hope the noise will gone.