Bad Omen for the future?

[Astyl 10+ year member]

So i was just messing around with my DMM today and i decided to do some reading of my battery, basically right now i have stock wiring, stock alternator, and a optima redtop under the hood.. thats connected to a dinky 400 watt rms sony amp pushing two amateur 12's... with the car turned off the voltage goes from 12.5 to 11.9 within like a 2 minute period and keeps declining.. with the car turned on the voltage hovers around 13.2 - 13.4, where it should be at 14.4 correct?

Is this a bad omen for the future? considering im wanting to get a eD Nine.1 @ 1200 watts rms and like 60% efficency, instead of this 400 watt rms sony amp? im guessing i need to upgrade bigtime before i can even think about it

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[Immacomputer 10+ year member]

Your battery is probably on it's way out. Also, don't take your DMM's measurements to be the word of God. They are usually off unless you paid over $75 for it.

 

[Neostar63 10+ year member]

just a question, but does the amp ever turn off. Maybe your remote is hooked up wrong and the amp just never shuts off. Take a look at that.

 

[TypeRBass 10+ year member]

Your battery is probably on it's way out. Also, don't take your DMM's measurements to be the word of God. They are usually off unless you paid over $75 for it.

i'll disagree with that. my cheapo walmart $10 one reads the same as my expensive one.

 

[CBFryman2 5,000+ posts]

For AC or DC? some cheapo ones dont have a true RMS voltage reading.

 

[helotaxi 5,000+ posts]

Since there is no need for an RMS reading on DC (since it doesn't exist) that is moot for this discussion.

Playing the system drains the battery, plain and simple. The voltage will drop with the system playing and the car off, there is no way around it. The fix to this is to not play the system with the car off. As far as voltage with the car running, 14.4 is not a hard an fast number. Different cars have different voltages set in their regulators. Most Fords, for example, will see a max of 13.8V. Factor in the fact that you haven't upgraded any of the wiring under the hood and you are probably losing some volts and thus power to wire and ground resistance, lowering your number at the battery even further. Until you've upgraded the big 3 none of your measurements really mean anything.

 

[Immacomputer 10+ year member]

i'll disagree with that. my cheapo walmart $10 one reads the same as my expensive one.

Awesome! You got a great buy then.

 

[azbass 5,000+ posts]

pwnt