JL Audio MC Factory Install -- Alternator Whine

Hey all,

We have some serious alternator whine on the factory installed setup in our 08 X1. Sounds fine when boat off, but basically unusable when engine running.

Not sure if any of the many amp settings are off, or if the factory messed something up on the install?

How does one diagnose?

Here is what's in the boat, and the settings it came with. 4 speakers in cabin, 2 towers speakers, one sub -- all JL stuff except Clarion head unit. MC factory install. Only one battery on boat, but should still be possible to get it work me thinks.

Pointers would be much appreciated. Gracias.

verify no power wires are close to your rca's, you might want to re run your own wires away from ones that look suceptable. Make sure you have solid grounds. Ive noticed this on a demo test 08 x2, I dont think they know how to best wire these boats.

Determine which part is injecting this radio frequency. Start by only having only one amp turned on, check for the same issue. work your way through all the variables.

(Message edited by canecorso on March 29, 2008)

fb I had an RCA connection cause some noise last year. At least you got to ride.

It came that way from the factory and you paid top dollar to have it. So take it back to the dealer and let him fix it.

thats the issue the dealer sometimes is the one to install all that stuff, there boat pros not audio, hopefully they can find it for u without not too much down time.

Doesn't look like factory install

I had what I thought was alternator whine. It was coming from the blower motor. Motor runing=blower on= whine through my speakers.

i have a loud deisel truck with subs and i had to by really expensive cables and wire so it didnt pic up engine noise. what im saying is they might have cheaped out on your wires, and they might not be insulated that well. are your wires gold plated, insulated.etc??

uh oh. Not another alt whine issue...

Then let the dealer send it out to a local audio store and let Master Craft or the dealer pay for it.

Have them move the deck's constant power and ground to the same power point as the amp uses and your problem is likely to disappear. Running the deck power or ground off the instrumentation harness is the most common mistake boat dealers/manufacturers make. Try a temporary wire first...

Thanks all for all the input. Have not had a chance to get back in the boat yet, but will for sure run down some of the leads.

Yeah, I have no problem taking it back to dealer, but figured peps on here generally know what you are talkig about, so if there are any obvious things to look at I'd do that first.

Much appreciated.

I too was not happy with MC on how they wired the radio and amp (2008 X2). I had to pull the amp power out and rewire it because they had it running at least 2 feet paralell with the rca cables and speaker wire. They also used at least 20 feet of wire and had it folded up beside the ballast box. I also moved the radio ground with the amp. This fixed all of my hissing. Another problem was that the power and ground of the amp shared a their posts with the ballast power. The whine was even worse when I ran the ballast. Now the amp is wired directly to the first battery.

My dealer is 4 hours away so it was quicker (and cheaper) for me to fix it. I have always been a MC man, but I lost a lot of respect for them when they violate stereo 101 rules.

Remember they are a boat builder and not a stereo shop with specialized training.

I am more than willing and more than likely to "tweek" my stereo..

Are those amps mounted to the floor, and what drivers (size and type) are you cutting to 120Hz?

I also see one of the X-overs set to lowpass and it is cut to 120Hz. What size is the sub?

(Message edited by olSkoolTige on April 01, 2008)

No, walkway wall under dash.

Don't have boat right here -- whatever standard JL sub that come in these. Anyone?

Greg -- as far as them not being a stereo shop -- perhaps, but they then should not pretend to be one either...

(Message edited by fbroen on April 01, 2008)

(Message edited by fbroen on April 01, 2008)

Sorry if that isn't very specific Steve. As my initial questions probably give away, I know next to nothing about audio stuff... Filters are set to whatever they came as...

Many people have different taste in music and settings but a crossover point of 120Hz is a little high for what I prefer. I usually run interior components down in the 85-100 range, and the sub in the same range with some overlap. Tower speakers I set a little higher.

Thx all again for advice. When I get a chance to get in the boat, will run down the leads and settings. Will let you all know how it goes.

Get some cheese and enjoy yourself.