My Amp grounds through the Rca's anyway to fix?

**Dragonlove** · 08-18-2008, 10:43 AM

This is a continue part from this thread:

http://www.mp3car.com/vbulletin/car-...battery-2.html

I found out that my amplifier grounds through the carputer via the Rca's, i found this out by pulling the ground from the amp, the light was still on and i could still play music, i then removed the Rca's and the amp went off.

What can i do with this? i even tried to ground the amp with shorter cables + smaller lenght on them, the grounding points is good enough cause their factory made.

Somehow the ground from the amp only want to go through the Rca's to the Carputer.

Could it be i need some other Rca cables? should there be resistance in the Rca cable's?

**barnyard** · 08-18-2008, 12:48 PM

Is the point where your ground wire attached to the car clean (no paint)? It should be bare metal, don't just assume that the bolt is grounded through the threads.

**Dragonlove** · 08-18-2008, 02:36 PM

Originally Posted by barnyard

Is the point where your ground wire attached to the car clean (no paint)? It should be bare metal, don't just assume that the bolt is grounded through the threads.

As i said it's a factory made grounding point, bare metal, i have 2 bolts in the trunk where the carputer which is made for grounding things.

**nobb** · 08-18-2008, 03:29 PM

Maybe the RCA outer shield is grounded to the main ground of the amplifier? It seems that alot of designs do this to reduce noise. As long as everything is running properly, I wouldnt worry about it. Might be a good idea to check that the main ground has lower resistance than the RCA ground so that the power goes through the main ground and not through the RCA.

**Dragonlove** · 08-18-2008, 04:44 PM

Originally Posted by nobb

Maybe the RCA outer shield is grounded to the main ground of the amplifier? It seems that alot of designs do this to reduce noise. As long as everything is running properly, I wouldnt worry about it. Might be a good idea to check that the main ground has lower resistance than the RCA ground so that the power goes through the main ground and not through the RCA.

It's not normal excactly, there's a lot of popping and crackling and i also get a lot of alternator noise then the engine is running, i measured the Rca cables and there's absolutely no resistance whatsoever through them, so my question is, are there Rca cables that has built in resistance? i read something about 75ohm or something.

**WuNgUn** · 08-18-2008, 04:45 PM

Usually, one end of the interconnect is grounded (drained) thru the amp...this is typical.
PLEASE do NOT run the amp with the main ground disconnected...unless you want to fry things!

**Dragonlove** · 08-18-2008, 05:42 PM

Originally Posted by WuNgUn

Usually, one end of the interconnect is grounded (drained) thru the amp...this is typical.
PLEASE do NOT run the amp with the main ground disconnected...unless you want to fry things!

Don't think i'll fry anything with this little amp, it measures only 100*52*150mm and gives around 20w rms x 4, pretty mutch the same as a standalone HU does, it even has the same wire size as one.

By the way, do you mean that it's supposed to carry ground through the Rca cables? and if so, will better cables remove the noise maybe?

**crusetech** · 08-18-2008, 05:50 PM

http://www.crutchfield.com/S-MMV67p2...aspx?I=127SNI1 would be a good place to start.

**Dragonlove** · 08-18-2008, 05:58 PM

Originally Posted by crusetech

http://www.crutchfield.com/S-MMV67p2...aspx?I=127SNI1 would be a good place to start.

Yes i already ordered one of those:

http://www.bilradiospes.no/m/shop/?p...id=m436&vn=736

But as i read this is only a bandaid solution.

**Sonicxtacy02** · 08-18-2008, 06:27 PM

its no solution at all.. i have the same problem and that will NOT remove all of the noises. The real solution would be to find how to isolate the ground in the rca cables.