Ibanez TB412S 4x12 w/funny jacks....

[acorkos]

a guy brought me his ibanez 4x12, switchable between 8-ohm stereo and 4-or-16ohm mono, similar to the modern Marshall 4x12 arrangement. one of the plastic threaded bushings broke off one of the jacks. No problem....zip zip...desoldered and installed a new jack. I went to meter the outputs to verify the combinations of impedences....i got some wacky readings. I took the back panel off and metered each speaker...all normal around 15-16 ohms.

i had a closer look at the jacks....they are wired backwards from a typical cliff-style jack. on the ibanez jacks, the switch is on the other side of the jack compared to the cliff-style. i tried pulling the contact elements off of a cliff jack to see if i could swap them around, but i can't get them off without destroying them. i guess i am calling ibanez in the morning....

[Enzo]

Can you replace both jacks, but mount them on the other side of the pc board? The whole board will now be a jack's height away from its previous position, but if there is room, and the jacks are the only mounting for the board, why not?

[acorkos]

i thought of that, too, but there's also a dpdt slider switch between the 2 jacks, and i can't see a way to swap those trace connections. maybe i can panel mount a separate switch w/wires to the pcb...?? i think that will work

[Enzo]

It was just a thought.