High end boat stereo question
 

Good customer with a new Formula just spent 5K with a very reputable stereo guy on upgrades,speakers,amps ,subs,etc,all the good stuff. But when the engines are running and it's cranked up there is lots of feedback thru the speakers. He claims low voltage on the batteries and he's not responsible. Both batteries read 13 volts. I am not a stereo guy so I need some input before I call BS. Why would weak batteries cause feedback,wouldn't the system just shut down? :(

Re: High end boat stereo question
 

I've seen this problem with altenators that didn't put out enough juice. Did he upgrade the charging system?

Re: High end boat stereo question
 

He Needs To Separate The Power Wire From The Patch Cords. The Two Running Together Will Create Engine Noise.

Re: High end boat stereo question
 

Add A 1 Farad Cap That May Wor`k If It Is The Voltage.

Re: High end boat stereo question
 

This is an 07 Formula 330SS with twin 496's,group 24 starting battery,group 31 house battery,and group 24 for genset starting. Stereo guy wants us to replace the batteries before he comes here to see if there is another problem. I don't mind doing that for a good customer but it's alot of trouble if that can't be the problem. For the record,I'm not involved,the customer contracted with the stereo guy. Both engines start fine,everything else works. Do I call BS on the weak batteries and have him come here and solve the problem?

Re: High end boat stereo question
 

Tell the stereo guy you'll replace them but if that's not the problem HE owes you the labor for the service!

Re: High end boat stereo question
 

Do you have a couple batteries you can swap from another boat ? if thats the problem then replace them.

Re: High end boat stereo question
 

When running the batteries should read more than 13 volts. How many amps (amplifiers) and what kind of wattage are they? A capicator will keep the voltage more even and not suck the battery dry every time the bass hits but I hear your problem is noise when running , correct? If it's feedback only when the engines are running it's a wiring issue. As By U Boy suggested make sure the patch ( rca ) cables are a min of 2 ft from the amp power cables and any other heavy guage power cables that may run through the boat. It could just be a bad rca patch cable. If it sounds ok with the engines off and the batterys are fully charged , I'd suspect the wiring before the batteries or charging system. If while the engines are running and the stereo bumping the voltage goes below 11.5-12 v , then time for an upgrade there too. If I did 5g system for a customer and it had some noise I couldnt leave it like that! Shame on the stereo guy!

Re: High end boat stereo question
 

I have plenty of batteries in stock,that's not a problem. And swapping them out is just a minor labor issue,no big deal. I guess the question is,is the stereo guy right,can weak batteries cause this feedback,or does he need to do some of the things BY u Boy mentioned?

Re: High end boat stereo question
 

Good point. Why do they sound good when it's not running? Voltage should be higher when running, right?

Re: High end boat stereo question
 

Going to plug in the shore power,turn on the built in battery charger for a few hours,then see if there is still feedback. If so, it is not a battery problem.

Re: High end boat stereo question
 

http://www.installdr.com/TechDocs/999502.pdf

My guess is a grounding issue

Re: High end boat stereo question
 

Thanks,Kevin. My thoughts exactly.Kind of like if I pay a plumber what he asks to fix my toilet and it still doesn't flush,it's his problem to make it flush,not mine. :rolleyes:

Re: High end boat stereo question
 

Just remember that battery charger will most likely put a ac humm over the stereo. Turn it off when testing sound quality. With the batts fully charged you should get some time to test before they flatten a bit depending on how many amplifiers and wattage.

Re: High end boat stereo question
 

If You Don't Find A Problem With The Rca Cables Or Power Source Pull The Amps And Have Them Bench Tested. It's A Possibility That The Amps Or Amp Has A Bad Power Supply.

Re: High end boat stereo question
 

It sounds like you have a "ground loop" issue, which means two grounds with different resistances. Try grounding the radio with the amplifier ground. For temporary purposes, run the stereo ground wire straight to the amplifier ground terminal at the amp. If the noise goes away or gets better then that is the problem. You don't have a voltage issue.

Re: High end boat stereo question
 

Thanks for the help guys. Another example of the power of OSO. Will let yall know what my stereo guy finds. Thanks.Robert

Re: High end boat stereo question
 

:drink:

Re: High end boat stereo question
 

It's not the batteries, make sure you have a solid CLEAN ground.

Re: High end boat stereo question
 

Wow, so caps magically create voltage??? :rolleyes:

Re: High end boat stereo question
 

I agree w/ the ground issue. It is RARE to get engine noise from a boat. REAL rare.
The only other thing it "could" be is: crappy electronics or maybe cheapo RCA connectors.
Does the "feedback" increase as the volume is turned up? If so, it is coming from the radio. If not, then the noise is being introduced thru the amps.

BTW: in this case, disregard my signature. I own a Audio / Video store. Used to do mobile electonics for 15+ years. :p

Re: High end boat stereo question
 

No, but if the noise is coming from the power cables, a cap "may" possibly filter the noise out.

Re: High end boat stereo question
 

A capacitor stores voltage and gets used at peak demands such as a bass note. This levels the demand for power from the alternator/battery.

Re: High end boat stereo question
 

About 1 Fahrad for every 1000 watts if my memory serves me right and capacitors (much smaller of course) are also 1/2 of a crossover network. They block lows, so if there is a low freq hum or ground loop originating before the cap in signal/voltage flow, it should filter it out.

Re: High end boat stereo question
 

THATS NOT WHAT I WAS TRYING TO SAY. BUT IT WILL HELP WITH BATT VOLTAGE WHEN THE AMP HAS A LARGE DRAW IT WILL COME FROM THE CAP AND NOT THE BATT. :D

Re: High end boat stereo question
 

I might suggest to the stereo company that you are looking to strategically align with several vendors to encapulate all of your clients possible boating needs. I might further suggest to them your committment to your client and share your concern regarding the difficulty you're experiencing resolving this problem. As you are dealing mostly with high-net-worth individuals, you'd presume this stereo company would be very interested in becoming the referral company for each of your clients stereo needs.

See if that gets them to move... if not - move on to one that does.

Custom Car Stereo here in Houston does all of the professional athletes and high-net-worth folks cars, trucks, buses, boats etc.... Maybe they will have a referral for you if those guys don't work out.

Steve (scarabfan) is the owner.

Joe

P.S. Steve, send me my referral check, please! :D :D

Re: High end boat stereo question
 

no :evilb:

Re: High end boat stereo question
 

Thanks for the help. The installer has admitted it is not a battery problem and he agreed to handle it for the customer. Once again,the power of OSO comes thru. :p

Re: High end boat stereo question
 

Hey Robert,
My battery is dead, could that be caused by my radio?

Re: High end boat stereo question
 

No,one of your puppies chewed thru the battery cable :drink:

Re: High end boat stereo question
 

BS from the installer. If the system had weak batteries the amplifiers are designed to shut off so they do not damage the speakers. Any good installer would know that. It is feedback from a poor wiring job and not placing them in the right location garuanteed!

Re: High end boat stereo question
 

Talk about bad Karma,as we were taking the boat back to the owner's boathouse,one of the 496 rods decided to separate itself from one of the pistons,leaving the bilge full of oil and coolant.We couldn't hear the stereo noise over the sound of a rod knocking :( As we wait for a new warranty long block from Merc,the stereo guy will have plenty of time to fix the stereo.Sometimes I wish I had a son so I could forbid him to go into the boat business :rolleyes:

Re: High end boat stereo question
 

When checking amplifier voltage drop issues, test voltage at the amplifier not the battery. Also test the ground difference at the amp and at the battery. This easy test will answer most power questions. An ungrounded amp can pull ground off the radio thru the RCA cables and obviously cause problems.

Re: High end boat stereo question
 

RCA Patch cables often cause this. I have even seen high quality patch cables that were not soldered properly. I used Monster Cables in the Cigarette. No noise issues. Hopefully this will help. Make sure the grounds are tight and that the ground wires are at least the same gauge or larger then the power. Power should not run near the RCA cables.