Engine whine in tower speakers

I recently hooked up tower speakers in my boat. I am running 2 tower speakers with a kicker 850.2 and running 4 cabin speakers through a small generic amp. I only have one RCA output coming out of the stereo so I'm using RCAs to a JL audio line driver with the variable out to an amp and the fixed out to a 2nd line driver and then the other amp, all so i can have seperate volume controls for cabin and towers. All sounded great until I started the boat and I have insane engine whine coming from the tower speakers. i have simplified as much as possible and tried running my ipod through rcas directly to the amp running the tower speakers and still engine whine only when the boat is running. I'm confused as hell now so if anyone has an idea of how to get rid of this whine i'd appreciate it.

could be bad ground or gain too high

gain is set at only half. i have a 4 gauge ground and have tried it at the grounding plate and at the battery.

I have heard of people using a ground loop isolator but i don't know if this would work in my case as i'm not completely sure of how they work. the only rca's that are currently being used is rca's directly to my ipod.

i would definitely just ground it to the battery post i you can. i'm assuming the answer is yes, but you do have your power wire fused right? i'd just call your local shop and ask them what they think. i used to have that problem in my car.

All grounds must go to a common point. All positves must go to a common point. If you have dual batteries and a dual battery switch then all positives go to the switch and not the batteries.
See if the gains are too hot. You can try a ground loop isolator but its only putting a band-aid on an inherent product or installation problem. Its better to get to the root of it. A small stray strand of wire can cross grounds or grounds can be reversed or something that creates a short at the amplifier output can then manifest as noise in both channels. Is the ipod using a plug-in cigar power supply? An MP3 may have a common ground on the headphone out where amplifiers have above ground inputs. If you've got noise with an ipod going directly into the amplifier at least you won't have many items to circumvent., isolate and substitute in order to prove the culprit.

David
Earmark Marine

Check the amp "ON" setting on the amp. I have a kicker 550 and had the same issue. My amp was set to turn on with the stereo signal and would basically amplify any little noise. Engine noise, ballast pumps, etc. I set the setting on the amp to remote (turns on with 12vdc) and no longer have an issue with noise. I knew I didn't have a grounding issue, since I just upgraded amps and all my wiring basically stayed the same. GL.

Tony

throw in my 2 cents.....I had a ton of issues with ground noise. tried everything. I isolated the issue down to my HU. I switched the ground off my HU from the battery to one of my amps...problem solved. electricity will follw the path of least resistance. Long ground runs will inherently casue ground loops if you have multiple components. It's a pain to deal with. I spent $$$$$ trying to fix issues two years ago.

Definately make sure the head unit is grounded directly to the battery. I had the same issue a couple boats back and have never had an issue since. Just cut the ground wire that is going to the common ground and use the screw on the back of the head unit to ground directly to battery or wherever you are grounding your amps. do not use the common for any component as you will be getting the whine from the alternator, and pumps.