Factory Wiring In MX212AR Appears Incorrect

LezPawl

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Hi Folks,

I am in the middle of a speaker swap for my MX212AR and noticed that the wiring in it does not look like any of the wiring diagrams that I've seen for either series or parallel for 2 speakers. I don't have an electronics background so I could be missing something so I'm asking for help. I purchased this cab new from Sweetwater so this wiring is straight out of the box. My understanding is that the two 16ohm, Seventy-80 speakers *should* be wired in parallel to give the rated impedance of 8ohm for the cabinet. You can see in the picture that the pos and neg leads go from the jack to the top speaker and then from those same connectors on the top speaker directly to the bottom speaker. I tried to measure ohms using my multimeter at the jack plate in this configuration but the measurements were wildly all over the place.

For reference I was using Celestion's wiring diagram for parallel.

IMG_0095.jpg

Thanks for any help!
 

fitz

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For reference I was using Celestion's wiring diagram for parallel.
That Celestion diagram just shows the red (+) wires and black (-) wires meeting at the jack.
Your configuration has them meeting at the top speaker.
Marshall is just using less wire to save $0.03.
No difference in connectivity.
1658620848589.png
 

LezPawl

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Thanks for your help! I figured it was probably my woeful lack of electronics understanding rather than a mistake at the factory ;-) I wonder why the other diagrams don't take the same approach for a less complex wiring solution? I did find a diagram from stewmac that had this exact same setup so they get it.
 


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