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chutch
05-21-2010, 12:19 PM
Hello everyone,

Ok so I just upgraded my stereo system and am having some serious alternator whine. This is the first time I have installed an audio system and never really new of it till now. Wondering if anyone can help me fix my problem. Sounds great when the boat is off but you canít even listen to it when the boat is running. All you hear is the whine so it is bad.

Here is what I am running:
Rokford Fosgate 12Ē Marine Sub (M212S4) New
2 Rockford Fosgate 8Ē Marine Midrange speakers (M282) New
Kenwood Headunit (KMR-440U) New
Kicker Amp (ZXM700.5) New
Rockfor Fosgate 1 Farad Capacitor (I am not 100% sure this is working correctly) New
Boss 530 Tower Speakers with light rail (old)

Pretty much everything except the tower speakers are new so I would hope that the problem isnít any of the components. Spent some good money on all the equipment and I was really upset yesterday when got in the boat for the first time and couldnít listen to the stereo. Donít know if it would help or not but I could sketch down the wiring diagram and maybe someone could look at it and tell me if there is something that sticks out there. Again this is the first time I have ever wired a system up but donít think I am a complete idiot. Seemed pretty straight forward when I did it. I guess I must not have something grounded out right or maybe something is not hooked up correctly.

Any help would be greatly appreciated.

Thanks,
Chris

philwsailz
05-21-2010, 12:53 PM
Put a sketch together, so we can see what you did.

I usually recommend that the radio's power wiring be removed from the helm electrical, to be wired staright to the amplifier's power terminals. This gets all stereo components at the same opearting voltage and ground potential and goes a long way towards making things quiet. What size power and ground wire are you using? FOr a ZXM700.5 you need to be using 4 ga for both power and ground, with both run to the battery.

Gains: Where do you have them set? This is the biggest issue with whines and pops and noise. You want your gains as low as possible. Generally with the gains turned up only a little bit, turn the radio up until it starts making crunchy distortion sound and then turn it back down a little. With most radios, this is at about 75% of total volume. Then turn the amp gains up until you start hearing similar crakling distorted sounds, and then turn it down a little. This process provides the best method of establishing unity gain; the place where both head unit and amp distort, at the same time. With unity gain, the gains are not turned up so high that they allow all he whines and noises through, yet not too low so that you don;t get max power out of the amp.


Post up your diagram and let's review. WE can get the nosie out for ya, with a little double-checking and probing.

Let us know-

Phil
Kicker

chutch
05-21-2010, 01:08 PM
Hey Phil,

Thanks for the info!

I am using 4 Ga wire. It runs directley off the battery to the Cap then into the Amp. The negative from the amp then runs into the Cap, then out the cap back to the battery.

I don't know anything about gains so maybe this will be a quick fix. Or I hope so. I didn't know what to set them at so I have no idea where they are set at. I will have to check that. Guess I need to read up on what the gain actually does.

I like the idea of running the power and the ground of the head unit back to the amp. That just makes more sense to me. Right now they are just run to a power block and a ground block that all the other gages are hooked too. I will sketch up what I have done and post it a little later. At work right now.

philwsailz
05-21-2010, 01:17 PM
Ahhh, if you did not touch the gains, they are probably turned totally up.

The probable best setting will be somewhere between 9:00 and noon as on a clock. Turnig the gains down will remove a lot of noise and allow you to turn the radio up a lot more before anything clips.

Since you did not set the gains, you probably did not set the crossovers. Make sure AMP1 and AMP2 crossovers are set to hi-pass. These are slider switches on the end of the map. Then the x-over knobs on the face of the amp need to be set to 8o Hz or so. Same thing with the SUB x-over. LEave bass boost totally off for AMP1 and AMP2 and do not turn it up more than again, somewhere between 9:00 and 12:00 as on a clock.

Let me know what else you need help with after you make these setting changes, and oh, let us know if the whine went away!

Phil
Kicker

mmandley
05-21-2010, 03:20 PM
Hey Phil,

Thanks for the info!

That just makes more sense to me. Right now they are just run to a power block and a ground block that all the other gages are hooked too. I will sketch up what I have done and post it a little later. At work right now.

Thats your problem right there boss. DO NOT ground the stereo to the boat ground block with your gauges.

You must run all your stereo grounds to the Battery Negative. This is not a car and there for you can not ground the stereo to the ground block under the dash.

Run all your grounds to a Distrobution block with only stereo gear and then run that to the negative terminal. Or just run it all directly to the battery ground. Try that and ill almost guarentee your whinning will go away.

chutch
05-22-2010, 11:48 PM
Phil,

You are the man. Hooked the ground up to the amp and turned the gains down and no more whine. I just turned the gains down all the way for now because I didn't get a chance to do much more. Hopefully I will get a chance to mess with the gains on Monday.

One problem I did notice is that when I gave the boat throttle the volume went down. Don't know if that has anything to do with the gains but may be another problem. I am hoping when I get the gains at the correct level it will not do that? Is that a possibility?

Thanks again for your help. If I were still living in Oklahoma I would buy you a frosty beverage from Eskimo Joes!

cab13367
05-23-2010, 02:49 AM
chutch,

Please read the how to below from Phil on the proper way to set amplified gains. I think you will find it very helpful.

Al

http://moomba.com/msgboard/showthread.php?t=9889

mmandley
05-23-2010, 10:31 AM
Phil,

You are the man. Hooked the ground up to the amp and turned the gains down and no more whine. I just turned the gains down all the way for now because I didn't get a chance to do much more. Hopefully I will get a chance to mess with the gains on Monday.

One problem I did notice is that when I gave the boat throttle the volume went down. Don't know if that has anything to do with the gains but may be another problem. I am hoping when I get the gains at the correct level it will not do that? Is that a possibility?

Thanks again for your help. If I were still living in Oklahoma I would buy you a frosty beverage from Eskimo Joes!

Honestly i don't think your problem is solved. I think all you did was lower your overall volume by gaining the amp down and the whine is there still you just don't hear it as much. I would still seriously look into where you have it grounded.

chutch
05-24-2010, 01:10 AM
mmandley,

I hooked the ground into the amp as I said above. What do you mean I should look into where I have it grounded? It is now on the cable that runs back to the battery. Is that not right?

mmandley
05-24-2010, 04:28 AM
mmandley,

I hooked the ground into the amp as I said above. What do you mean I should look into where I have it grounded? It is now on the cable that runs back to the battery. Is that not right?

Sorry buddy i might have mis read your last post. I thought it was only saying you adjusted the gains. I missed you saying you relocated the ground directly tot he battery. My only concern was grounding the stereo the ground buss bar under your dash.

chutch
05-24-2010, 08:46 AM
Sorry buddy i might have mis read your last post. I thought it was only saying you adjusted the gains. I missed you saying you relocated the ground directly tot he battery. My only concern was grounding the stereo the ground buss bar under your dash.


No problem. I thought you might have missed it but wanted to make sure I was doing it right. Going to hopefully mess with the gains tonight. Do I need to have the engine running when I do it? If that is the case I hope it doesn't rain.

mmandley
05-24-2010, 12:27 PM
No not at all on the engine. Set it up how you want it. Then if you got a fake a lake you can start the engine to see if you have a whine. You can also just turn on the bower fan, heater, things like that and if the while is there you should hear it.

chutch
05-25-2010, 01:04 AM
Got the gains set tonight. Everything seems to be good so far:).

philwsailz
05-25-2010, 12:08 PM
In the event that you have noise when you are running, or if you have pops or buzzes from pumps, blowers, fans etc. please let me know. I have a fix we found for a boat builder that works real well. Basically we use a capacitor in parallel with the offending load. This takes the back - EMF or the noise that the load puts on the power wiring and shunts it to ground.


Let us know once you run the boat.

Phil
Kicker

chutch
05-25-2010, 04:21 PM
In the event that you have noise when you are running, or if you have pops or buzzes from pumps, blowers, fans etc. please let me know. I have a fix we found for a boat builder that works real well. Basically we use a capacitor in parallel with the offending load. This takes the back - EMF or the noise that the load puts on the power wiring and shunts it to ground.


Let us know once you run the boat.

Phil
Kicker

Thanks again for your help. I will hopefully get out tomorrow night. I will let you know how it goes.

chutch
05-27-2010, 08:27 AM
Had the boat out last night and still have a little bit of alternator whine at low volumes. Don't notice it as much at higher volumes. Could my gains be a little high or is this something else?

mmandley
05-27-2010, 10:14 AM
Generally any whine threw the stereo is a lose or bad ground and the stereo is the most sensitive part and having an amp on it will obviously amp this bad sound.

When you have the boat sitting with the engine off. Can you play the stereo and use all the accessories and have no whine? If you have wine then you will have to track it down to what item you turn on that cases the whine.

If nothing then what amps are you using? Try unplugging one and playing the stereo when you had the whine before. If its there on all the amps when running them one by one then its in the boat. If it goes away at any point then you have a amp with a bad ground, or a floating ground internally in the amp.

This is going to take some work to track down but the bright side is you will really understand your electrical grounding system lol.

Lastly im sure you checked this but just to be sure. Stereo and Amps need to be on a separate battery and grounded to this separate battery. Other wise all your troubleshooting can be a mute point as the whine would be a primary grounding issue.

chutch
05-27-2010, 03:32 PM
Generally any whine threw the stereo is a lose or bad ground and the stereo is the most sensitive part and having an amp on it will obviously amp this bad sound.

When you have the boat sitting with the engine off. Can you play the stereo and use all the accessories and have no whine? If you have wine then you will have to track it down to what item you turn on that cases the whine.

If nothing then what amps are you using? Try unplugging one and playing the stereo when you had the whine before. If its there on all the amps when running them one by one then its in the boat. If it goes away at any point then you have a amp with a bad ground, or a floating ground internally in the amp.

This is going to take some work to track down but the bright side is you will really understand your electrical grounding system lol.

Lastly im sure you checked this but just to be sure. Stereo and Amps need to be on a separate battery and grounded to this separate battery. Other wise all your troubleshooting can be a mute point as the whine would be a primary grounding issue.

Right now I have one battery that runs everything. I have thought about getting a second battery to run the stereo on. Is this something I should go ahead and do?

mmandley
05-27-2010, 04:52 PM
Right now I have one battery that runs everything. I have thought about getting a second battery to run the stereo on. Is this something I should go ahead and do?

I would reccomend it as the stereo can drain a battery pretty fast and the last thing anyone wants is to be stuck on the water with a dead battery.

You can still do all the amp troubleshooting and make sure things are grounded properly. You can even pull your car battery and hook the stereo to it for trouble shooting. The main thing here is lets find that whine. Ive had that whine before and i now its irritating and once you hear it your ears get tuned into it and it even more irritating LOL.

philwsailz
06-01-2010, 11:24 AM
I have posted this diagram elsewhere, but it never hurts to put it up again.

Whining, pops and ticks are most often caused by the head unit being wired at a different voltage potential with respect to the amp. This is way too common, unfortunately, and it is an easy fix.

See the drawing. When you move the power for the radio to the amp, you remove the voltage potential difference. This eliminates the "vehicle" for the whines, pops and clicks....

The key to understanding all of this is that you want to wire the radio's power wire, (all of it, red, yellow and black) straight to the amplifier's power connections. Any voltage difference, or ground plane difference, (which actually shows up as a voltage on the ground wire}) is eliminated. ADDITIONALLY, there are big filter capacitors just inside most amps, in front of the power supply, and the proximity of these large filter caps can provide a filtering benefit to the radio wiring.

A point to make. This drawings show both a relay that is triggered by the ignition accesory circuit from your key switch and anoter common option, which is a simple rocker switch. The simple bottom line in all of it is that you want the yello wire to always see +12 volts, and you want the red wire to have some means of being switched. IF this is at all confusing, let me know and I can dexcribe it further or walk you through your installation...

Hope this helps

Phil
Kicker

chutch
06-02-2010, 11:21 AM
It sounds like I may need to move my red power line. I have it going to a switch but I bet the switch is powered by the boats wiring harness. Not really sure though. My yellow line goes all the way back to the battery. Anyway, I got a lot of the wine out by moving the ground to the ground line going back to the battery. Plus got the gains set correctly too.