Portable speakers hooked to car battery?

[johans.m]

Hi people.

I own a "Logitech Pure-Fi Anywhere 2" (**broken link removed**).
The festival I'm planning on going to this year lasts for roughly one week. Thus I expect the battery of my stereo to run out long before that.

My thouhts are if it's possible to directly hook up a 12V car battery to my little baby. When she's pugged in with the regular charger she receives 12.9V at 1.39 amperes. Which corresponds to rouhly 17-18 watts if I'm not mistaken.

My questions are these:

1. Would it really work like that?
2. Should I build a protective system of some kind?
3. Some years temeprature in the shade reaches 30 degrees celsius. Issue?
4. Can I do rough calcuations on how long a car battery would last? I honestly don't know how many miliamperes the speaker battery is


In advance I'd like to thank anyone who could shed light on this issue.

 

[Sceadwian]

Directly to a battery it should probably be okay, though you may not get full volume out of it as the battery dies. Hooked up to a running car it may be a ltitle more risky as it'll receive approximately 13.8 volts. I personally think it should be safe, if the voltage is high you just have to be careful near max volume otherwise the circuit may receive more current than it was designed to.

 

[johans.m]

Hi Sceadwian. Thank you for your prompt response. This stereo runs off of an integrated battery pack. Does that make any difference when hooking it up?

 

[audioguru]

The little battery or the wiring in the stereo might catch on fire if the internal battery is discharged then connected to a car battery.
Disconnect the internal battery when using the car battery.
Be prepared to call a tow truck when the car battery does dead. I recommend a separate battery.

 

[Sceadwian]

For the use you intend to put it through a deep cycle or marine grade battery would be best, not a straight car battery. They're designed for cranking amps not long term durability through deep discharge. That being said you can still use a car battery every now and then without harm. The longer the battery spends bellow 80% of a fully charged state the shorter it's lifespan will be.