Resistance across speakers.

[Witek]

I have two speakers, both of them rated at 16ohm. I was checking the resistance across the speakers, one of them spits out 16.1ohm, perfect. The other puts out 13.2ohm. Could this mean that this particular one is defective, dying or even dead?

[billdurham]

Speakers are rated in Impedance, not DC Resistance. Impedance is measured in ohms just like resistance, but its not the same thing. If the speakers are the same make and model, there could be a problem, but if they are different brands.. probably not.

BD

[Witek]

Speakers are rated in Impedance, not DC Resistance. Impedance is measured in ohms just like resistance, but its not the same thing. If the speakers are the same make and model, there could be a problem, but if they are different brands.. probably not.

BD

They are both the same make and model, but I beleive they are from different time periods. They're celestion g12m's, one of them has a silver back the other has a gold colored back (the identifying sticker).

And is there a way to measure impedance using a standard multimeter?

[billdurham]

Interesting... its possible that they would have a different dc resistance and be the same impedance.

No, you can't measure impedance with a standard meter.

sorry I can't be much more help, I just don't remember enough of that physics course to help you more. The difference in dc resistance is probably because they changed the gauge wire in the voice coil. The one with the higher reading has more wire in the voice coil, but probably smaller wire.

BD

[Old Tele man]

Rule-of-Thumb: R(dc) = 80% of Z(ac)

...so, if it's an 8-ohm speaker, you'll probably measure about 6-6.5 ohms dc-resistance on your ohmmeter.