pulsating sound in stereo system

I bought a new boat to me with 4 tower speakers, 4 interior speakers and 2 12" subs. From what I can see under the dash, the deck is running the interior speakers, 1 amp is running the tower speakers and the other amp is running the subs.

Subs seem to work, the tower speakers kind of work sometimes but mostly crackle and the interior speakers aren't putting out sound.

What I do get is a pulsating sound through both amps, and the gauges all bounce with the sound.

This deck isn't a marine deck. I am wondering if it got some water in it when it was uncovered for a while at the previous owners place. I didn't get a chance to try it out before I bought the boat. He said it all worked...

one other thing is the battery is suspect. I did charge it and it will start the boat but seems to lose power pretty quickly if I'm not running the motor.

I think the deck is cooked. Is there any way to the test that out without having to buy another deck?

Rugglesworth said:

I bought a new boat to me with 4 tower speakers, 4 interior speakers and 2 12" subs. From what I can see under the dash, the deck is running the interior speakers, 1 amp is running the tower speakers and the other amp is running the subs.

Subs seem to work, the tower speakers kind of work sometimes but mostly crackle and the interior speakers aren't putting out sound.

Click to expand...

Did you swap the tower speakers with the subs to see if any of the tower speakers are blown?

Rugglesworth said:

What I do get is a pulsating sound through both amps, and the gauges all bounce with the sound.

Click to expand...

A shorted voice coil (blown speaker) can cause that.

Rugglesworth said:

one other thing is the battery is suspect. I did charge it and it will start the boat but seems to lose power pretty quickly if I'm not running the motor.

Click to expand...

Two amps are going to burn a lot of power. Need an oversized, our separate battery to power the sound system

Rugglesworth said:

I think the deck is cooked. Is there any way to the test that out without having to buy another deck?

Click to expand...

Your symptoms point to a blown speaker.
Remove interior speakers from deck to see if that helps. Swap outputs from deck to amps. See if problem moves from one output to the other

Once I removed the remote from the first amp that powers the tower speakers the noise went away. The subs and second amp are working fine. Bizarrely only one speaker off the deck is currently working....

Whew, hope we never anchor close together, no offense but hate loud music on the water...

airshot said:

Whew, hope we never anchor close together, no offense but hate loud music on the water...

Click to expand...

I'm 48 I feel you on that. I bought the boat this way, I don't crank the music but I like things to work properly. It's pissing me off looking at it. It's more for when I take my boys out for a cruise on our lake or watersports with their buddies.

Rugglesworth said:

I'm 48 I feel you on that. I bought the boat this way, I don't crank the music but I like things to work properly. It's pissing me off looking at it. It's more for when I take my boys out for a cruise on our lake or watersports with their buddies.

Click to expand...

I hear ya, I am the same way, can't stand it when something doesn't work right.....even if I don't use it...it bugs me that it doesn't work !!

Rugglesworth said:

Once I removed the remote from the first amp that powers the tower speakers the noise went away. The subs and second amp are working fine. Bizarrely only one speaker off the deck is currently working....

Click to expand...

The picture of the wiring says it all.

Audio equipment is very sensitive to ground loops and increased resistance in the wiring.

All wiring on a boat needs to be done with marine rated wire and water proof connectors (crimps) to protect the integrity of the system.

dingbat said:

Did you swap the tower speakers with the subs to see if any of the tower speakers are blown?

A shorted voice coil (blown speaker) can cause that.

Two amps are going to burn a lot of power. Need an oversized, our separate battery to power the sound system

Your symptoms point to a blown speaker.
Remove interior speakers from deck to see if that helps. Swap outputs from deck to amps. See if problem moves from one output to the ot

Click to expand...

dingbat said:

The picture of the wiring says it all.

Audio equipment is very sensitive to ground loops and increased resistance in the wiring.

All wiring on a boat needs to be done with marine rated wire and water proof connectors (crimps) to protect the integrity of the system.

Click to expand...

yeah, looks like it was wired by the Prince of Darkness. I am going to hook up each speaker to the deck individually, towers included to see what comes out and report back. May be a few days before I get back to it as I'm putting a new carb on the motor

Rugglesworth said:

yeah, looks like it was wired by the Prince of Darkness. I am going to hook up each speaker to the deck individually, towers included to see what comes out and report back. May be a few days before I get back to it as I'm putting a new carb on the motor

Click to expand...

dingbat said:

The picture of the wiring says it all.

Audio equipment is very sensitive to ground loops and increased resistance in the wiring.

All wiring on a boat needs to be done with marine rated wire and water proof connectors (crimps) to protect the integrity of the system.

Click to expand...

Ok sounds i tested all interior speakers and tower speakers. They all work off the deck. So the amp was cooked. The jackass wired all 4 of the tower speakers through one wire and into the amp and then jammed the rest of the speakers into 2 channels. Meaning 10 speakers into 2.l channels while it was a 4 channel amp. What a goon. I'll get another amp and wire the towers to that and the interior speakers to the deck and then I should be golden