battery amp hours

baggyman · Soul Rider Joined: 19 Aug 2004 Posts: 331 City: Vegas

i guess that the higher rating on a battery means the longer you would be able to run your stereo is that right? i have found a couple batteries with 115 and 120 amp hours any idea how long these run with out going dead? is thier some type of calculaiton that i can plug in my wattage and get an idea of how long i can run?

wesgardner · Posted: Oct 25, 2004 6:34 am Post subject:

Hey baggyman,

watts = volts x amps.

if your stereo draws 10 amps and your battery can provide 115 amp/hrs, then you can run your stereo for 11.5 hrs - this in theory....

Wes

MrBlean · Posted: Oct 25, 2004 10:16 am Post subject:

Don't confuse the power rating of your stereo with the power it consumes. It's probably only 10-20% efficient so it will consume 5-10 times the power that it's rated at producing. Note, as Wes stated, it's power consumption in amps that's important. Unless you put a meter in your power line to the amplifiers and measure it at typical volume you can't be sure of the consumption.

Also, our perception of sound is inverse logarithmic so twice the volume takes a helluva lot more than twice the electrical power to produce. So, you could run for a couple of hours at half volume and only a few minutes at full volume.