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Magnepan 1.7 dspNexus 2x8 DSP Crossover project

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HAL:
Made a trip to NC to pickup a second pair of Magnepan 1.7's.  Crazy enough this one has the opposite speaker to mine needing repair, so I can make one mirror image pair of the two with all the driver foils working. 

I already have the DSP crossover design for a fully working pair from the one good one I had, so can finally hear the fully working speakers.  :)

Doing it this way, it costs less that just the two way shipping of a pair for rebuild.  :o

HAL:
Magnepan 1.7 pair #2 have the silver side stiles as compared to pair #1 with the black side stiles.

Now to remove the sock and passive crossover and install the replacement wiring and connector plate.

HAL:
The side stiles were removed and sock on the intermittent 1.7 speaker and had the staples pulled, so easy to pull up the sock.

This one has a break in the woofer foil that had a repair that is not holding. The bigger problem is the woofer foil is delaminating in areas and the mylar is wrinkled. This would need a complete rebuild, so putting it aside.

I looked through the sock with a light on the working speaker and see a bit of the same foil delamination problem, but no wrinkles in the mylar. Once I remove the side stiles and staples, will be time to see if some glue cleaning and reapplication will fix the areas of problems.

HAL:
Now that CAF2024 packing is completed, time for some ideas on how to repair the 1.7's.

I wired up a 12VAC toroidal power transformer to a 250Ohm resistor.  Wired the resistor to the positive side of the foil.  Only using the inphase lead of the toroid with my ELFIX to see where the AC field stops. 

The foil break seems to be at one of the folds close to the negative terminal of the supertweeter.  Will use some acetone to remove the paint and glue to inspect the fold.

I purchased some grounding paint that is carbon based to see if it will complete the foil circuit.  I thought about silver, but that and aluminum are not a good combination, so the flexible carbon paint might work.  If I paint the carbon trace first, I do have some silver conductive paint that could go over the carbon to increase the conductivity, but not directly contact the aluminum foil.

I do have a ribbon replacement kit from Magnepan, but that is not an easy project from watching the Magnepan LRS build video on YouTube.

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