audio voltage

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=106568
Printed Date: May 14, 2025 at 1:04 AM

Topic: audio voltage

Posted By: PATPJRICK
Subject: audio voltage
Date Posted: August 04, 2008 at 3:05 PM

I know this sounds like a stupid question, but I just want to confirm....

When your car is running, but at idle, the voltage should be anywhere between 13.7 and 14.1? correct?

And when your car is off with the key in the accessory position a voltmeter should read between 11.7 and 12.1? correct?

Replies:

Posted By: i am an idiot
Date Posted: August 04, 2008 at 3:18 PM

Some vehicles will show 12.5 volts at idle. But at driving speed will go to around 13.8. No numbers are set in stone. What kind of problems are you having?

Posted By: Big Dog
Date Posted: August 04, 2008 at 4:01 PM

Automobile batteries have six cells of 2.1VDC that are connected in series, which produces a total voltage of 12.6 volts. With all accessories turned off and key turned off you should get at least 12.6VDC, less than that is not good.

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Posted By: PATPJRICK
Date Posted: August 04, 2008 at 6:25 PM

When I drive at night with my stereo cranked up the headlights dim. I went through 1 Optima red top within 4 years of time and just recently replaced it. I was hoping that I didnt have to replace it soon because of the dimming headlights or replace an alternator. I know a simple solution is to just turn down the stereo....but when a good song comes on you gotta rock out to it.

After installing my voltmeter gauge today it was between 12.9 and 13.3 depending on the bass notes....and the AC was on because it was hot as hell outside today...but when I turned the AC off and left the stereo at the same volume it stayed near 13.3

Posted By: i am an idiot
Date Posted: August 04, 2008 at 7:18 PM

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