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pstoool
09-17-2008, 11:11 PM
:applaud:>>Edgewound...The DC resistance range of the 126A and 122A is 4.5-5.5 ohms dc.


Hi all,

About the DC resistance ranges of the 126A, if the ohm meter shows 4.4 ohms across the woofer - what does that mean? This woofer is considering good or bad?? :blink:

Thanks for the help:bouncy:

pstoool

badman
09-19-2008, 01:06 PM
:applaud:>>Edgewound...The DC resistance range of the 126A and 122A is 4.5-5.5 ohms dc.


Hi all,

About the DC resistance ranges of the 126A, if the ohm meter shows 4.4 ohms across the woofer - what does that mean? This woofer is considering good or bad?? :blink:

Thanks for the help:bouncy:

pstoool


The 4.4 reading is fine, but unfortunately, this doesn't mean anything. I snagged a pair of 122A for $75 (needing refoam), and after foaming and testing, found that they were victims of the dread AlNiCo demagnetization.

This makes them useless for some alignments, but fortunately, I didn't have a restoration in mind, just wanted some tasty AlNiCo 12"s at a nice price.

Testing for demagnetization can be done by VAs/Sensitivity testing, or by comparing published Qts spec vs. measured. If measured is significantly higher (and the driver works properly), it's lost a significant amount of motor strength.