Stereo Guys

I had a customer that bought a couple AGM Dekas and a slightly higher powered alternator last year. His stereo worked fine last year but when he was getting his boat ready this year the stereo would turn off when he turned it way up. He has 4 PDX amps running off 2 AGMs and an alpine deck that may or may not be hooked up to his starting battery. He also uses the Remote turn on wire from the deck to the amps. He says the whole thing turns off(deck and amps). The batteries checked out completely fine.

Any typical things I should have him check or thigns that could cause this? I told him to check all his amp connections and go through the deck wiring to make sure it is all good. I didn't tell him but suppose I should tell him to make sure and charge up the starting battery all the way.

Oh yeah, not sure if it matter but his interior speakers are running off deck power.

Would the deck shutting off for whatever reason turn off the amps as well?

Brett I think you have him on the right track....

If your loosing the deck power, I think your problem begins there. If it shuts off it will take down the amplifier(s) because the remotes are all tied to that trigger. My gut feeling from what you have shared is faulty deck psupply.

A very easy check would be to bypass the deck completely and use an ipod with a 3.5mm jack and plug into the RCA inputs of the amplifier(s). I have a hunch even on high volume his system will play fine especially if you checked out the battery situation.

tell him to be careful of the ipod volume output because he can very easily take his system to full power and crush the speakers.

once this is established, you can get a better handle on the faulty device and start changing things out accordingly.

-Brian
Exile Audio

Had a similar problem on mine. The amps are cutting off because the head unit (and remote lead) are cutting out. Turned out that I had upgraded all the wiring in my boat except for the main ground in the dashboard. Just beefed that up to 10gauge and everything works great now.

Brett,
Btw, sorry for calling you Bill in the other thread. I got Bill and PolarBrett mixed up.
It has to be something common to all amplifiers and the source unit if they are simultaneously shutting down...and that is likely the source unit. Certainly the source unit may have a different voltage threshold for turn on/off than the amplifiers but if the voltage is maintaining a high level I doubt that is the cause. Most source units are DC direct and don't have a switching power supply at all in order to have a power supply problem. It could be water damage where the short caused by corrosion isn't a factor until more current is flowing which explains why the problem occurs as the volume is increased. Also, most source units feature an internal BTL chip amplifier that will not tolerate a 2-ohm load or two speakers paralleled on a single channel. As a result, the source unit would fall on its face hard and possibly power down and in turn shut down the amplifiers. Disconnect the source unit from the cabin speakers. Check the grounds. Make sure the source unit is not procurring its ground from the 'above ground' RCA shields or interconnection with another component. Look for mineral spots or a white film on the source unit chassis. Make sure that more items and more current draw wasn't placed on the source unit remote out lead. I would limit this to a 2/10th of an amp maximum. Perhaps a relay is in order here. That is the short list to begin with.

David
Earmark Marine

Thanks Dave. I will forward him the info.

Also, is the alternator regulator okay? A sure result if the voltage was actually too high when the boat is running. The source unit could shut down in the same way as low voltage.

David
Earmark Marine

I am not even sure he had the boat running. It is kind of weird because it worked fine for him last labor day weekend(last time he used it I think) and the first time this year it had the problems I described.

Winter/summerization, shock, vibration, corrosion, UV, batteries sitting discharged long term, high humidity under the boat cover with water left in the bildge, winter storms and horizontal driven rains, temperature and humidity extremes and so on. I've seen factory crimps on the heavy alternator/starter feed just fall off in your hand after being trouble free for several years. Its a boat and stuff just happens.

David
Earmark Marine