life of a battery

[childofthewind]

hello samba community.

ok. so, i just got installed a lovely "sound system" in esther. not knowing anything about this sort of thing i dished out (too much) $$ for a couple sweet boston acoustics 6x9s and a 2 channel boston acoustic amplifier which the installer put under the passenger seat. he didn't ask where i wanted it.. i actually assumed he'd put it under the bench seat where the 6x9s went but of course it made sense to put it right next to the battery and out of sight and out of the way.

when i had another stereo place put in my kenwood stereo a couple months back they said that, due to the wiring, i would have to manually turn on and off the stereo. so, i can listen to it without the keys in it, etc.

i'm sorry to be asking what may be an obtuse question, but: how long can i listen to the stereo (with ipod connected to it, say) without compromising the (only) battery i have? i've yet to have a problem and i've listened to the stereo sometimes up to two hours and it starts, no worries. but i'm unfamiliar with how much power a 2 channel amp draws from the battery.

should i look into a second battery? i don't really power anything else in the van when it's not running so i'm hoping one will be sufficient.

thanks!
_________________
1987.5 wolfsburg hardtop; 2.1

“As for me, I am tormented with an everlasting itch for things remote." - Melville

[toomanyveedubs]

It kind of depends on a few things.

How old is the battery?
How loud are you listening?
How well does the alternator charge?

I would install a voltmeter, a second battery, or both.

You can hook up the accessory 12v on the radio to your ignition so it comes on and off with the key, or even have it wired to the 'key in' circuit that chimes if the key is in and door open.

Search the forums here for instructions.

[childofthewind]

[quote="toomanyveedubs"]It kind of depends on a few things.

How old is the battery?
How loud are you listening?
How well does the alternator charge?


good questions. in all honesty i do not know how old the battery is. i bought the van a few months ago and don't see, in the stack of receipts that came along with it, anything with a new battery on it. i bought it from a used car dealer who bought it from an auction. i think the owners who donated this van to oregon public radio did a lot of the work so maybe some receipts were lost.

i don't listen to my music too loud these days as it's cold and rainy so i'm just inside my van during long breaks at work. i will be heading to a warmer climate soon though and will maybe crank it up a little.

recently i had a lot of work done on my van at a reputable vw shop including a pre-trip check. one of the things they did was check my alternator and said it was good and strong. i may be presumptuous in thinking they checked the battery, too... i didn't think to ask.

i guess this may be one of those "trial and error" lessons in life.
_________________
1987.5 wolfsburg hardtop; 2.1

“As for me, I am tormented with an everlasting itch for things remote." - Melville

[childofthewind]

it sounds like a lot of people put a second battery under the driver's seat and/or install a voltmeter. better to be safe than stranded, i guess..
_________________
1987.5 wolfsburg hardtop; 2.1

“As for me, I am tormented with an everlasting itch for things remote." - Melville

[Ahwahnee]

An easy & cheap way to have a voltmeter is to pick up an inexpensive multimeter (e.g. Harbor Frieght for a couple of bucks), cut off the pointy test lead ends and connect them to a 'cigarette lighter plug'.

Set the meter to the 0-20 volt range and plug it into the lighter to monitor the battery. Turn the stereo off when the voltage drops below -- 12v??? -- maybe others will know how low you can go.

My guess is that you will be able to listen to it a long time (if your battery is healthy).

[GrindGarage]

The battery in your van is there mainly to start the car. I like it to have that single task. When it comes to having draws without the engine running I would prefer them to be on a dedicated deep cycle battery that is designed for the use. If you plan on using your stereo with the van not running it may be a good idea to get a second battery and relay.
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-cliff

91 Vanagon AUTO
97 Single Port EJ22 all smallcar.com

[Vango Conversions]

I left my sterio on for about 8 hours or so and it fired right up. It was a 50w x4 reciever with the radio on and the volume really low. I bet an externan amp would probably pull more juice than just a head unit though, even on low volume.

[Wildthings]

I would be worried that you might have a pretty sizable ghost load even when the stereo is turned off. When the unit hasn't been on for a couple of hours, how hot is it? If it is warmer than ambient temperature you have a ghost load. You may either have to rewire the power to the unit or read the instruction manual and find out how to turn it completely off. On a lot of units you can just depress the "off" button for a second or two to kill the ghost load.

[childofthewind]

[Ahwahnee]

For under 5 bucks it's a pretty handy battery monitoring tool if you aren't interested in more involved instrumentation:

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