How is it possible?

(liljohn) · (liljohn) **Join Date: May 2007** 07-05-2011, 2:12 PM

This weekend we were lake bound the entire time. A friend of mine who just got done redoing his whole stereo provided the tunes for the beach. Now pay attention this is the important parts. On Friday he played for 4 hours @ 1/3 to 1/2 volume. Skip Saturday. Sunday he played for 9+ hours at the same volume. in all of this playing we had two surf sessions that lasted about an hour and one lap around the lake that was twenty minutes. So a total of 13+ hours of play time with only 1 1/2 hours of alternator charging time. His battery bank is two 6v batteries. The system is all Exile and consists of 2- 800.4`s /1- 2500.1 /and a harpoon. so four amps total.

Does this really seem like it should work? I thought for sure we would be switching to his reserve battery bank. What are your thoughts? Am I under estimating the batteries or is his system really that efficient?

(ottog1979) · (ottog1979) **Join Date: Apr 2007** 07-05-2011, 2:23 PM

I'm just wondering why the boat time and stereo time aren't reversed!

(you_da_man) · (you_da_man) **Join Date: Sep 2009** 07-05-2011, 2:35 PM

Those 6v systems can have a lot of play time ability. There's a couple members on here using two 6v batteries and getting over 300+ amp hour capabilities, of course other electronic factors come into play but I don't think that 13hrs is unreasonable.

(murphy_smith) · (murphy_smith) **Join Date: Dec 2005** 07-05-2011, 2:39 PM

It had to have been the batteries!!

(wakekat15) · (wakekat15) **Join Date: Jul 2005** 07-05-2011, 2:39 PM

Quote:

Originally Posted by ottog1979

I'm just wondering why the boat time and stereo time aren't reversed!

LOL, most excellent point!!

(liljohn) · (liljohn) **Join Date: May 2007** 07-05-2011, 3:22 PM

The ride time would have been reversed but every tube pulling S.O.B. was on the lake by 9am. We know better than to think we will get alot of ride time on holiday weekends. That is why we pitch a camp on the beach.

So what you guys are saying is it sounds totaly possible? I had herd stories of a guy running two group 29`s with the same system at full volume for 8+ hours and said no way! After this weekend I am thinking maybe he was honest.

(05mobiuslsv) · (05mobiuslsv) **Join Date: Apr 2006** 07-05-2011, 3:30 PM

I think it was the highly inefficient exile stuff

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(bill_airjunky) · (bill_airjunky) **Join Date: Apr 2002** 07-05-2011, 4:08 PM

John, first of all let me be the first to tell you I don't even claim to know how or why these systems work the way they do. I can follow directions, but have no idea why or if the 6 volt batteries or the efficiency of the Exile system is the reason why they lasted sol long.

But you remember Lawrence's red/black LSV at Banks? He has a pair of 6 volt batteries in his boat.... in addition to the 12v starter battery. Neither of the 6v batteries are hooked up to his alternator. He ran for 3 days at Banks, plus another day at Entiat, before he plugged in his charger.

BTW, he's a high voltage electrician for Boeing. I can hook you two up if you want to talk shop with him about how or why his system works. He's down in Kent.

(cadunkle)

You sure he doesn't have a separate starting battery and a ridiculously high amp alternator?

(david_e_m) · (david_e_m) **Join Date: Jul 2008** 07-05-2011, 7:45 PM

Think about a golf cart with two large people and two sets of clubs running for 15 to 20 miles or 3 to 4 hours. While there may be three times the batteries in the typical 36 volt system that is quite a load as compared to moving a few light speaker cones.

David
Earmark Marine

(05mobiuslsv) · (05mobiuslsv) **Join Date: Apr 2006** 07-06-2011, 8:31 AM

Explain the guy banging for 7 hours straight at 75-100% volume with the boat off with 2 srm-29's before the stereo shut off. 15 min later the boat still started, weird.

(wotan) · (wotan) **Join Date: Jul 2008** 07-06-2011, 9:07 AM

I'm pushing 2 big, inefficient and old 4-channels and a 2200watt brutus. I've got two cheap group-29s and a starting battery (325ah capacity, total.) I went hard for 8 hours this weekend without any voltage drops. Heat was my only enemy.... Started running into the tower speakers cutting out after 4-5 hours of 75% volume playing. The 2-ohm load was tough on my poor old PPI amps thermal protection. Working on fans and remounting the amps to try and get some more airflow before this weekend. Never expected that my batteries would last that long!!

(bill_airjunky)

Quote:

Originally Posted by cadunkle

You sure he doesn't have a separate starting battery and a ridiculously high amp alternator?

I talked to him last night. He has a stock alternator & a starting battery. The 6 volt batteries he's charging with a separate charger that he stores in the truck.
The weekend we were at Banks, he probably spent 5 - 8 hrs out riding everyday, for 3 days straight. He never pulled the boat from the lake so never had a chance to recharge. Obviously he wasn't playing the stereo all day everyday, but still pretty impressive that it went that long. Not sure what amps he's running but he has two big NVS tower speakers setup that are just stupidloud.

LC said he'd love to share more about the setup if your interested. Paul knows how to get a hold of him or you can PM me.

(chexi) · (chexi) **Join Date: Jul 2009** 07-06-2011, 10:42 AM

I would like to know what 6v batteries people are using.

(05mobiuslsv) · (05mobiuslsv) **Join Date: Apr 2006** 07-06-2011, 11:48 AM

Quote:

Originally Posted by chexi

I would like to know what 6v batteries people are using.

Interstate U2300