JL Audio System Noise --- Help!!!

**saounyang** · 03-23-2008, 03:07 PM

So I have a JL 12w7, 1000/1 amp, 300/4 amp, mids, lows, tweets, JL and stinger RCAs, and a HC600 2nd battery, with a pioneer 5900 HU.

It is all installed into a 98 Honda Civic Hatchback EK.

The sub, 2nd battery, and amps are all in the trunk. I have a separate ground for each amp and 2nd battery. My HU is still using the OEM ground.

I have tried moving the ground for my 4 channel amp to different locations but no matter where i place it, I get ground loop noise. (It's not the whining noise).
I have sanded thru the paint to the metal then grounded and even tried oem screwed locations such as the spare tire screw and the rear seat screw. All no-go.
I bought a multi-meter to help but I am now more confused with what to do with it.

If any of you has any suggestions at all, please share. Thanks!!!

(If you have a similar car - where did you mount your ground?)

**boomintrac** · 03-23-2008, 04:27 PM

Are your amps touching metal anywhere? that could do it
Aron

**saounyang** · 03-23-2008, 04:40 PM

Originally Posted by boomintrac

Are your amps touching metal anywhere? that could do it
Aron

not that i can see.... i thought that too, but there is carpet behind the back seats so they are not in direct contact

**greatwhite** · 03-23-2008, 04:56 PM

First, what does the noise sound like?

Does it change with engine speed?

Is it there when the engine is off?

Does it change with components turned on and off? (ie:fan, etc)

Do you have power wires running parallel with signal wires? Or bundled together?

try unplugging the RCA's to each component (seperately) and see what happens.

Try disconnecting power to each amp seperately and the 'puter.

Ground loops are a real PITA sometimes, you just have to keep chasing it..........

Good luck

**dMand** · 03-23-2008, 05:31 PM

ground all your components in the same location with the correct wire gauge size.

**saounyang** · 03-24-2008, 04:17 PM

Originally Posted by greatwhite

First, what does the noise sound like?

Does it change with engine speed?

Is it there when the engine is off?

Does it change with components turned on and off? (ie:fan, etc)

Do you have power wires running parallel with signal wires? Or bundled together?

try unplugging the RCA's to each component (seperately) and see what happens.

Try disconnecting power to each amp seperately and the 'puter.

Ground loops are a real PITA sometimes, you just have to keep chasing it..........

Good luck

-Doesn't change with engine speed. It is not there when engine is off. Does not matter if components are off/on. RCA wires are parallel w/ power cables except the Rem cable. Thanks so far man!

**saounyang** · 03-24-2008, 04:18 PM

Originally Posted by dMand

ground all your components in the same location with the correct wire gauge size.

I have heard different things - to ground in different locations and then at the same location.....

which is better? just tired of sanding and adding another hole to my car

**greatwhite** · 03-24-2008, 04:55 PM

Originally Posted by saounyang

-Doesn't change with engine speed. It is not there when engine is off. Does not matter if components are off/on. RCA wires are parallel w/ power cables except the Rem cable. Thanks so far man!

Well, that's some progress.

If it doesn't change with engine speed, it's not alternator whine. Same with fan, AC, etc.

Not there when the engine is off indicates it's something grounding out through your audio equipment or there might be some noise induced into your rca's from the power wires.

Try seperating your power and signal wires and see what happens.

Something that a lot of people forget is that modern cars all have electric fuel pumps and they've got to me some of the "noisy-est" motors I've even dealt with. Installing your equipment, running wires parrallel to the power path or grounding near it usually produces mind numbing noise you can't seem to find no matter what tricks you use. If you've grounded your system under the rear seat this could also be a problem as that's where most modern cars have thier fuel tank and thus, the fuel pump and harness.

Grounding your components to the same point is usually good advice, it's makes all the gound paths equal in resistance, but it's not always the cure.

I've moved a ground point 6 inche before and cured a ground noise, sometimes it's just that simple.

The quality of your components might also be an issue if you have lower end stuff (amps, connections etc). There's a noise "floor" in every piece of audio equipment. Cheaper stuf fis usually noiser.......

Cheers

**crimpdaddy** · 03-24-2008, 10:49 PM

are you running component speakers? if so... where are your crossovers mounted? i had this problem once b4 in a vette. if the crossovers are too close to a power wire or just a random accessory wire... they pick up whine. kinda the same effect as if you were to put a neon light too close to an amplifier.

**funkyphil** · 03-31-2008, 10:03 PM

Sounds like your did all your homework for this one, so leaves me to believe it's either a bad amp? Or if you are using your oem head unit with a line converter (line to RCA), those are really pretty common to cause noise!

Rule of thumb always start by replacing your stock head unit first. Then upgrade from there. Even if you just go with a $200.00 Kenwood HU with RCA outputs your going to have a much better sound. Even from stock speakers. This is because the HU is the brains of your system!

Just my 2 cents.

Good luck!