Voice coils & amp wattage

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=42573
Printed Date: July 16, 2025 at 9:08 AM

Topic: Voice coils & amp wattage

Posted By: Thuan
Subject: Voice coils & amp wattage
Date Posted: November 09, 2004 at 2:09 AM

How can I tell if my voice coils are working properly? Also, how do I check to see how many watts my amp is putting out? Am I suppose to use a multi meter...if yes, then how am I suppse to check it with a multi meter?

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Thuan

Replies:

Posted By: Thuan
Date Posted: November 09, 2004 at 3:12 PM

anyone?

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Thuan

Posted By: DYohn
Date Posted: November 09, 2004 at 3:30 PM

What do you mean by "if my voice coils are working properly?" Do your speakers work?

You cannot directly measure power output from your amplifier with a multimeter. You can measure the AC voltage output and calculate the approximate effective average power by using the loudspeaker's average impedence and Ohm's law...

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Posted By: Thuan
Date Posted: November 09, 2004 at 4:12 PM

I meant if one of my voice coils are burnt or not (subwoofer). Do I just hook it up and make sure there's continuity within each coil? I'm not sure if my amp is working properly so I want to check everything before I send it back for another one.

Ohm's law...E=IxR?...that would give me Voltage = Amperage x Resistance right? But how do I figure wattage from that?

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Thuan

Posted By: jeffchilcott
Date Posted: November 09, 2004 at 4:25 PM

If you take your amperage and mulitply it times you current draw you will get wattage

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Posted By: DYohn
Date Posted: November 09, 2004 at 4:37 PM

Yes, read the DC resistance on each voice coil with your ohm meter. If the sub has two coils, they should both read about the same value. If they do not, the one that is significantly higher is probably burned.

Power = Voltage squared / Resistance. https://www.the12volt.com/ohm/ohmslaw.asp

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Posted By: Thuan
Date Posted: November 09, 2004 at 4:59 PM

Thanks guys.

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Thuan