Triple rails buckers?
What about this
quadruple rail model designed by an old friend of mine?
http://www.kcpi.fr/imagprod/newntm.jpg
LOL.
It's not necessarily the most powerful pickup but it's actually a good sounding one, BTW.
That said...
If I had to find the most powerful passive PU, I wouldn't trust its DCR: I'd start by measuring its inductance AND Gauss level, which are two more important parms IME... albeit they still not draw the whole picture.
So, the best test is to measure empirically the max output level of a passive PU and it's relatively easy to do: buy or borrow a multimeter, set it on voltage and if possible, ask it to memorize peak values. Then connect it to the output jack of the guitar with alligator clips. then dig the strings until the voltage doesn't rise no more...
For the record, one of the most powerful pickups I've measured with this method is a vintage Bill Lawrence spitting 1,2v with its humble 14k : after 30 years of use, it wasn't even fully gaussed and it hadn't the highest inductance (it was a 9,5H thing while I've measured some PU's @ 12H). But Bill known how to design efficient magnetic circuits, without too much Eddy currents.
The funny thing is that such an output voltage is not even reliable since it actually
changes according to the lenght of cable used to plug the axe (because the pickup, pots
and cable form a LRC circuit, displacing the peak power in the audio spectrum according to the overall capacitance involved).
That's one of the many reasons why the output level of passive coils can't be measured
absolutely, at the end of the day...
FWIW (no more than my 2 "dimes", probably). Good luck for those who will keep searching the most mighty bucker!!!

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