Finding Speaker Resistance

I tried searching, but must not be using the right queries.

How do you use a multi-meter to measure speaker impendence?

Thanks!

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impedance*

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Set the speakers to read ohms, take one probe and touch it to one speaker terminal, take the other probe and touch it to the other terminal.

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Top Secret, I can tell you but then my wife will kill me.

forbidden wrote:

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Set the speakers to read ohms,

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I want one of those!

Make that set the meter to read ohms......nice one Rob, teaches you to talk on the phone at the same time.

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Top Secret, I can tell you but then my wife will kill me.

And realize that the above will get you the DC resistance of the speaker, not the impedance.  Impedance is dependent on frequency and changes continuously.  DCR is always different from impedance, most times lower than rated impedance, but sometime higher.  It depends on the speaker.

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My meter just jumps to infinity, like the circuit is complete.  Am I doing something wrong?

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Perhaps they are blown. Why are you testing them to begin with?

Where is meter set on the ohm range?

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definitely not blown.  Maybe I dont know how to adjust my ohmeter.  All I see for adjustment is the needle itself and the red dial on the side.  Ill try playing with that

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Hahaha.  Rob, that's hilarious.  I didn't even catch that typo until I read the next post.

Are you trying to test for speaker leads behind a radio, or are you testing speakers themselves?  If you're testing wires, chances are you may have a factory amp, and need to test there.  You said the speakers are definitely not blown- how do you know?  Did you hook them up, and get sound?  If you're testing the speakers themselves, set the meter on a scale that can easily measure 4 ohms. 

It sounds like your using an old volt-ohm meter.  I suggest picking up a digital multimeter instead because it's safer.  That being said, if you must use an analog meter, here's how: Be sure the probes are inserted in the right slots on your meter- black to common, or ground, and red to ohms (not amps).  Set the meter on a resistance scale proper to measure around 4 ohms.  Now short the two probes together and calibrate to zero.  You should be ready for testing.

The analog volt-ohm meters are usually only useful if you're watching for voltage fluctuations- the needle can respond quicker than a digital readout.  Other than that, they should not be used to test wires in newer cars because, like test lights, they do not offer a high resistance, and could cause damage to sensitive electronics (set off air bags, etc.).

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My ex once told me I have a perfect face for radio.

The speaker is brand new.  I also tested my existing sub which is supposedly running at 1.9 ohms.  The ohmeter is brand new as well.  But both speakers were reading infinity.  Still cant figure out what i am doing wrong!

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Okay, you said your meter has a needle.  It sounds like you're using an analog meter on the wrong scale, and the needle is pegged.  This can damage your meter.  If you touch the leads together does it read zero?  If your meter is new, look in the manual for any clues.

However, I still suggest picking up a digital multimeter.  If you're going to be testing any wires in a vehicle- analog meters are dangerous like test lights.

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My ex once told me I have a perfect face for radio.

What's the make/model of the meter?

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Ok, so maybe i was remembering wrong.  When I touch the leads the meter reads zero, just like when i test the subs.

so, clarification - the meter reads zero.  So how do i calibrate the meter?  is it the red dial?

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the sub is DVC by the way

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It very well could be the red dial.  When you short the leads, you adjust it to read zero.  If your subs read zero, they're either shorted, or you could have messed up your meter by pegging the needle.

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My ex once told me I have a perfect face for radio.

Like I asked earlier,

DYohn] wrote:

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hat's the make/model of the meter?

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when i touch the probes together it reads perfect zero. 

GB Instruments  GMT-12A (brand new)

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Never heard of it.  I looked it up on the web and it appears to be a very cheap, very limited meter with only one ohm range?  What is the range (what does it say in green under the word "ohms"?)  In any case, I would guess it is simply not accurate or sensitive enough to measure low resistance.

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that might be true.  it says 1k, but i swear in the instructions it talks about a switch that you can adjust to just measure ohms instead of 1k ohms.

But the only switch is the red dial used to zero out the ohmeter

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