Can a DMM test speaker polarity

[ArrizX 10+ year member]

Okay, so I have this DMM





and I was wondering, because with my dads home theater, he thinks he has some wires crossed in the walls that we cant see or get to period.

So, if I unhook it from the amp, is there any way I can hook this DMM up to the wires and figure out which polarity is which?

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[ArrizX 10+ year member]

lol @ first response....

 

[Innovative:Cory 10+ year member]

No...unhook wires from source and use a small battery to "pop" the speaker... if it moves out with the + on the + and - on the - then you have proper polarity... if not then it is reversed..

 

[ArrizX 10+ year member]

How small are we talking? Like AA, or AAA?

 

[tommyk90 5,000+ posts]

How small are we talking? Like AA, or AAA?

9 volt.

 

[ArrizX 10+ year member]

Seriously? That wont hurt the speaker at all?

 

[zack39648 10+ year member]

no a 9v battery wont hurt the speaker like the other guy said it it goes out them you know the + is + and - is -

 

[ArrizX 10+ year member]

Hm, alright well thanks.

****, the package of this thing said automatic polarity testing.

Guess it was more towards battery or something.

 

[tommyk90 5,000+ posts]

Seriously? That wont hurt the speaker at all?

Nope, just don't leave it on there for extended periods of time. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[ArrizX 10+ year member]

Okay, thanks.

Awesome avatar BTW. Love that movie RIP Rodney Dangerfield //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[joeboxer5876 10+ year member]

or you can you the volt meter. set it to read ohms. if you get a negetive number, the you have the black touching the + and the red touching the -. if the number is positive, the you know you have the red touching + and black touching the -. make sure the volt meter reads negative and positive though. i know mine does.

 

[tommyk90 5,000+ posts]

or you can you the volt meter. set it to read ohms. if you get a negetive number, the you have the black touching the + and the red touching the -. if the number is positive, the you know you have the red touching + and black touching the -. make sure the volt meter reads negative and positive though. i know mine does.

Incorrect.

A DMM, when set to read resistance (ohms), does NOT show polarity.

And to be sure of this I went outside and took my DMM to a sub. Sure enough, no matter what side the postive lead was on, it read 1 ohm. No negative number.

A voicecoil is simply a piece of wire, no negative and positive sides. The DMM is showing the resistance of that wire. A voice coil only becomes positive and negative when there is a power source attached to it telling it what to be. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[SVTLightning01 10+ year member]

IIRC correctly, all the polarity checkers do is test a through connection. You pout the lead on point A and point B and it will beep if there is a connection from A to B. You can use it on your home theater. -|>|- is the setting on the meter.

 

[azbass 5,000+ posts]

I used to test polarity with my 12v batt from my drill. that never hurt the speakers.

 

[joeboxer5876 10+ year member]

i just tested that out and i was wrong. //content.invisioncic.com/y282845/emoticons/*******.gif.a649d21efc0d1fd4890a6428166586c1.gif

i will get off my a$$ and check stuff like that before i post again