the magnet core you posted is the 2415 - you can tell by the round "salt pepper" holes in the phase plug. To the best of my knowledge that driver was only used in the very early "G" series MI cabinets...
This was superseded by the 2416 which has the annular slits like all the other JBL drivers and is considered an improvement.
And the 2416H-1 driver's diaphram I think is just a tweaked 2416 with better adhesive and the tiny tiny air pressure relief hole in the back.
So now we need you to post *both* of the magnets to see if there is a difference before we strategize further. While your budget is always of concern, you *do* want to treat your left and right ears fairly..
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