Speaker white noise/buzzing

[mdolesh]

I have always had a slight buzzing sound coming from my 4 cockpit speakers. Last night I installed newer/better speakers and now I can hear it even more. I did some research and keep coming across ground loop isolators, but I think there is already one installed. The buzz happens even when the stereo is completely off. I tried turning the gain on both amps all the way down and that didnt change anything. The only time it will stop is if I turn the battery switch completely off. Here is a picture of the amps that power the 4 cockpit speakers. Thanks for the help!

 

[Fill Ess]

Did you try isolating the amps (in other words, power them off individually to see it's one amp or the other)?

Is it just the cockpit speakers, not the cabin?

 

[mdolesh]

No, I did not try that. Do you think one amp could be bad? I am contemplating replacing both 2 channel amps with a nicer 4 channel amp. No, its just the cockpit. The two speakers in the cabin run directly from the head unit and not the amps. They have no noise.

 

[scoflaw]

Try running the head unit ground directly to that amp ground

 

[mrsrobinson]

I assume this occurs when the engines are running/not running, both?

 

[mdolesh]

I honestly dont know if it gets better when the engines are running. I guess it could make it worse, right?

I just spoke to Crutchfield for a good half an hour about solutions. They think the power cables coming in and then splitting to the amps being the same gauge could be the problem. My plan is to remove the old amps and install a new 4 channel amp and a new ground loop isolator. I wanted to do this anyway...so we will see if it helps.

 

[mrsrobinson]

Yes, buzzing can occur with the engines running, I think from the plugs/wires.

I like your plan, you don't need 2 amps IMHO for cockpit speakers, one 4 channel should be fine assuming it's powering 4 speakers.

And I love Crutchfield customer service. I called them once from the boat when installing a new head unit and they walked me thru resolving my issue.

 

[dtfeld]

Are these the original amps? I had the same problem, tried all the things listed above and spent way too much time and money. In the end, it was amplifiers that had gone bad.

Replace the amps with a good marine amp of your choice. I found a JL Audio 6 channel that's plenty of power for the stock setup.

I would skip the ground look isolator for now.

 

[mdolesh]

Yes. Original. I agree and ordered a new amp. Why do you recommend I skip replacing the ground loop isolator?

 

[Fill Ess]

It would be easy enough to isolate one amp vs the other by pulling the fuses. I agree with @dtfeld that you would be better off with a nice modern 4-channel amp if one or both is the problem.

 

[Shaps]

It could be the amps, it could be the wiring, it could be LED bulbs the OP has introduced to the boat. It could be a bad ground. It could be an unshielded power cable next to the wires from the amp to the speakers...

I would start by isolating the amps one at a time and see it it is 1, the other or both. After that, id see if there are LEDs that are introducing the RF interference.
Then report back?

 

[mrsrobinson]

Can you remove the amps from the equation and just use the head unit for the speakers? Similar to what @Phil S is suggesting, though actually removing the speaker wire so it's not going thru the amp.

Looks straight forward from your pic, 4 screws. Start with one amp, test, still hear the noise, do the next amp, test, still hear the noise: sell the boat

 

[mdolesh]

It could be the amps, it could be the wiring, it could be LED bulbs the OP has introduced to the boat. It could be a bad ground. It could be an unshielded power cable next to the wires from the amp to the speakers...

I would start by isolating the amps one at a time and see it it is 1, the other or both. After that, id see if there are LEDs that are introducing the RF interference.
Then report back?

This might sound like a silly question...but can LED lights cause interference when turned off? I have replaced all of the lights with LEDs but last night there was still the buzz when all the lights were off.

 

[mdolesh]

Can you remove the amps from the equation and just use the head unit for the speakers? Similar to what @Phil S is suggesting, though actually removing the speaker wire so it's not going thru the amp.

Looks straight forward from your pic, 4 screws. Start with one amp, test, still hear the noise, do the next amp, test, still hear the noise: sell the boat

LOL - "Sorry honey, gotta buy a new (bigger) boat...those damn speakers are still buzzing."

 

[Fill Ess]

Sometimes you get lucky and it's an easy fix. When I bought this boat, none of the cockpit speakers worked at all. It turned out to be a head unit setting and new connections on 2 speakers. Now we are rocking 24x7x180

 

[Shaps]

This might sound like a silly question...but can LED lights cause interference when turned off? I have replaced all of the lights with LEDs but last night there was still the buzz when all the lights were off.

apologies there.
I agree, LED lights will not (or shouldn't) cause any interference if there is no power to them. Different then on but dimmed..
I was on a roll of listing possible causes and there may be several actually.

 

[Wylie_Tunes]

GLI's are bandaids and only mask the root issue, so I would avoid them if possible. They also only work upstream of where they are installed. So if the unwanted voltage is entering the system downstream of the GLI, it wont catch it. I read that the noise is there when the system is off. I would verify that by taking a voltage reading on the amps' turn-on terminal when the head unit is off. Should be 0 volts. Also make sure they the amps' power lights go out. Can even disconnect the ground cables. Sounds like the amps are staying on. If not, I suspect AC voltage is bleeding into speaker leads somewhere.

 

[mrsrobinson]

I li

GLI's are bandaids and only mask the root issue, so I would avoid them if possible. They also only work upstream of where they are installed. So if the unwanted voltage is entering the system downstream of the GLI, it wont catch it. I read that the noise is there when the system is off. I would verify that by taking a voltage reading on the amps' turn-on terminal when the head unit is off. Should be 0 volts. Also make sure they the amps' power lights go out. Can even disconnect the ground cables. Sounds like the amps are staying on. If not, I suspect AC voltage is bleeding into speaker leads somewhere.

I like this thought; however if the amps were staying on they would drain the batteries, right?

 

[ttmott]

I had a buzz in my last boat. Ended up being the RCA cabling between the head and amplifier. The cable was routed with another wire harness that had the VHF and radar cables. I unplugged the RCA jacks from the amplifier and the buzz stopped. I upgraded to a premium RCA cable and re-routed away from other wiring and devices.

 

[mdolesh]

Thanks for all the input and ideas. I am heading to the boat tomorrow to try to figure it out. I think the amp(s) might be the culprit. When I unplugged the RCAs coming from the head unit to the amp the buzz was still there. I also am curious about what Wylie mentioned...the amps staying on. I think they might be staying on when the head unit is turned off.