Troubleshoot low stereo playing time/battery issue

Ok, I have my system installed now.

I have syn1, 2 syn2's, and a syn4. I have 3 Deka31's for the stereo, (105 ah each I believe) and another fourth battery just for start, a switch, a VSR, and onboard charger. My boat guy told me to charge the batteries overnight on switch setting "0." I went out yesterday and the stereo only lasted less then an hour at pretty high volume. "1" is the starting battery and "2" is the stereo battery bank.

And would not play at all on the ride home with switch at "1 and 2." Weird?

I think I should get more time, what am I doing wrong?

The way I have my battereis/charger wired , if my main switch is set on "0" ( assuming you mean in the off position) Nothing will get charged. My switvch has to be set on "both".

Yea, that makes sense in my mind too, but I'm not experienced in these matters...I'm charging on "1 & 2" as we speak. Yes, sorry, in the "off" position, not "o." Doh!

Do you have a hand held voltmeter? If so run a couple of tests. Check the voltage with no stereo on and the boat running. Make sure your alternator is actually working. You can play with the switch some to see what happens when you switch it. Just make sure you don't move the switch to off while boat is running. Also make sure your selector switch is a newer one that connects to the circuit you are switching to before it breaks the old connection.

Thanks Brett, I was thinking of doing some sort of test like that too. I think if I have to get that in depth I will just take it back to my boat guy/dealer for prognosis. Everything is brand new.

I'm thinking I should be able to get at least 3 hours, maybe four, at pretty good volume level out of those batteries. My rough uneducated guess is that each of the amplifiers is running at about 20 amps, so 20 x 4 is 80 amps, and I have 3x105 ah's, so that about four hours. Obviously some additional amps running deck and 420, but whatever. I could be totally off too of course.

You don't have enough batteries, or good enough batteries for you setup. I think they lasted about what they should have. Your amps are drawing WAY more then you think they are. A lot of people say they can listen to their system for hours at high volume, but the majority cant. I can say from personal experience that the whole system, from batteries to alternator need to be upgraded to really be able to play for a while. I run a upgraded alternator and 4 kinetics and cant really play music for more than an hour at full volume before I need to start the boat, although I do have a 13w7 that can kill a normal battery bank with ease. With the upgraded alternator I can still play the music and charge the batteries enough to keep playing. I have an onboard charger that I use every time the boat is on the trailer to keep the batteries maintained.

I go to the delta a lot and chill on the beach and listen to all the different stereo's. The people that clan play for a long time have a boat full of batteries along with a good charging system to back them up.

Well, that is not very encouraging Jason! I dunno, seems like everyone is running 2-4 batteries. Maybe this needs a poll. I had no idea what a "13w7" was, but I googled it. Massive sub, I'm running the WS xs-xxx, which is also formidable at 850x1 off the syn1. I'm sure that's not helping.

I've seen my fair share of big systems and can guarantee you 2-4 batteries will not give you hours of listening enjoyment at high volume. You seem to have some good equipment that uses a lot of juice. There should some stereo guru's that will check this tread soon and can give you some better input.
I got 4 kinetics specifically meant to run systems and they don't last that long. I might get close to 2 hours with the motor off, but that's pushing it. I don't have a big system that needs a big battery bank, but even these 4 batteries that retail for over 1k still aren't enough to play for hours at a time.

I'm by no means a stereo guru, but I saved this spreadsheet a few years ago. Posted by another member. You should be able to calc what your alternator and/or battery drain will be given your setup.

I had to rename the file with a .txt extension. It is an Excel file. Copy and rename to .xls to open it.

Interesting...thanks for that. The spreadsheet is saying I should have 2.5 hours for an a/b amp, I think mine are g/h. So, it should be more then that I believe, theoretically.

I had to rename the file with a .txt extension. It is an Excel file. Copy and rename to .xls to open it.

How do you do that?

sucky, I don't have excel

Ok here is what I have exactly:
starting battery
3 Deka dc31dt Marine master deep cycle batteries for stereo
Promariner Prosport 20plus triple bank charger
VSR relay module (cut in 13.7v, cut out 12.8)
switch

Majority of people are running 2-3 battery stereo systems and getting decent hours of play time, even with the overrated Optimas. The Deka Group 31 Seamates are great batteries and very popular with stereo systems. Now if you're "that guy" in the party cove for hours on end then you may need a massive bank of batteries

I'm not really looking to be "that guy," but I'm also not looking to be the guy with the awesome looking 3some on his tower but can't play it for more then 30 minutes and has to sit there listening to everyone else's boat. I'm just looking to match my battery system to my stereo system to get those "decent hours of play time."

Any help appreciated. thanks...

Oh, and I have a stock 70amp alternator, but I'm told its folly to think an alternator will re-charge all these battery systems and better to have a sufficient battery bank/system and onboard charger.

Amp draw is very dynamic.

What kind of music do you listen too? large determining factor in how long you can play your stereo? IMO , I think you should get more than an hour of play time out of your current setup.

Before you jump to conlusions, check voltages on all your batt's. Make suer they are all fully charged beforee you leave the dock.

Check yrou wiring...espcially your HU wiring. Two boats ago, I had my HU inadvertantly pulling off my starting batt. It wont' last long if your HU is pulling power of it. It will start to cut out, causing everything else to cut out ( remote power to amps will cut).

I guess I will need to check those voltages, I am just assuming they are fully charged due to green light indicating such on my onboard charger.

I assume HU is head unit. I will check this issue but I think if my HU was pulling off my starting battery then this would affect more my ability to get started again. I didn't have any problem switching to battery 1 and starting up. I was playing the stereo while on setting 2, the stereo bank.

Originally Posted by brian_b

I'm not really looking to be "that guy," but I'm also not looking to be the guy with the awesome looking 3some on his tower but can't play it for more then 30 minutes and has to sit there listening to everyone else's boat. I'm just looking to match my battery system to my stereo system to get those "decent hours of play time."

Any help appreciated. thanks...

Oh, and I have a stock 70amp alternator, but I'm told its folly to think an alternator will re-charge all these battery systems and better to have a sufficient battery bank/system and onboard charger.

From what I can tell the way you plan on using your system you are correct. Your alternator isn't going to do much. By the way, that stock 70 amp delco 7si will put out 90 amps at room temp. I have no idea how hot it actually get in a wake boats engine compartment but you are probably getting a little more than 70 amps out of it.

Originally Posted by brian_b

Ok here is what I have exactly:
starting battery
3 Deka dc31dt Marine master deep cycle batteries for stereo
Promariner Prosport 20plus triple bank charger
VSR relay module (cut in 13.7v, cut out 12.8)
switch

The 3 Deka DC31's should have about the same 20AH of 3 6v golf cart batteries. I know you cant have 3 but every 2 group 31's is similar to a set of golf carts.

Another thing is that if your VSR doesn't combine the batteries tell it reaches 13.7v then it is hardly ever going to combine the way you are using your system.

I thought the VSR caused the alternator to charge one battery at a time?

Brian, my chargers popped the fuse in the power wire ( b/c of bad batteries) . the charger was showing the batteries charged ( greeen light) It wasnt' untill I checked the output of the charger ( after the fuse) I notice dhte fse was blown.

I will check the fuses, but all my batteries are brand new. checking the voltages as was also suggested would also resolve this issue I presume, if any.

The ladies usually play hip hop music I guess you would call it. I don't argue.

Well one thing to remember is AH ratings for audio batteries is pretty much worthless. AH ratings are determined by drawing small amounts of amperage for extended periods of time. Audio (especially bass) draws HIGH amperage at shorter bursts, unless you are playing a audio competition track that is all bass. So, with this said I wouldn't put a lot of faith in AH ratings for a audio bank of batteries. Its kind of like picking a battery because of the CA or CCA ratings. Those tests are very outdated (1918) and test the battery's ability to put a charge to the starter for 30 seconds. No one turns their ignition on for 30 seconds, because if you did you would burn your starter up.

One of the first things I would do is check the voltage of the batteries at full charge. When a AGM battery is fully charge it should read around 14.4V and then come down to a resting voltage of around 13V. 12.8V is fully charged and some batteries rest at different voltages. Our batteries rest around 13.2 or so.

Then I would check the voltage coming form the alternator, at your starting battery, and at your battery bank. If everything is working properly your voltage should be consistent at all three places.

What do you estimate the total wattage is for your system? Bass and mids/highs? If you get me this info I will try to get some time on our battery dyno and run your exact application on our Group 31 Batteries (D3100) to see what the results are. I could guess how long you should be able to play, but I would rather run it on the dyno to see for sure.

Ok I know this isn't an example of a Marine audio set up, but here is a great example of how Bass will draw current more than the mids and highs. You can see the voltage stay around 14V until the bass kicks in, and as soon as the bass lets up the voltage starts to climb again. http://www.youtube.com/watch?v=fCANaVPv5yM This is probably a 4k watt + system.

Nathan,
I think my boat "guy", Mike, spoke to you about my system and we are going to discuss getting some batteries from you.
It's my understanding you recommended one battery per amp; I'm running the following:
all Wetsounds
xs-xxx sub powered by syn1 at 850x1
In boats syn4 800 total
Pro80's by syn2 2x200 (400 total)
485 by syn2 700x1
so I guess 2750 total is being used of 3200 possible