Electrovoice 18" Woofer: smallish Magnet; only 2.3 ohms?


I’ve been watching some electro-voice drivers, from their Vintage Model E-V Six, drawn by the 18" woofers,
original specs say 8 ohms

https://products.electrovoice.com/binary/E-V%20Six%20EDS.pdf

 here’s a pair of the woofers

https://www.ebay.com/itm/254646609730?hash=item3b4a1ee742:g:y-gAAOSwk19fBH44

1. 2.4 OHMS? My vintage drivers, Crossover, and L-Pads from that era are nominal 16 ohms. I never measured them.

2. Smallish Magnet on 18"? My 15" paper woofers, 15W 37 lbs, have much bigger magnets.  (the 18" are 1/2" thick styrofoam).

https://products.electrovoice.com/binary/15W,%2015BW,%2015WK,%2015BWK%20EDS.pdf

https://www.ebay.com/itm/284098370766?mkevt=1&mkcid=1&mkrid=711-53200-19255-0&campid=533...

3. Mine is 16 ohms, I know they make a 8 ohm version, yet that one shows 3.5 ohms???

Help me avoid trouble by ignorance please,

thanks, Elliott
elliottbnewcombjr
I have four pairs of electrovoice speakers and none of them measure that way. The dc resistance is way higher than that in all cases so i would be leery of a fake 18 inch woofer for sure especially if the magnet is small, ev did not use small magnet assemblies in any of their woofers.
speakermaster

they are original E-V 18WS Woofers, used in both the E-V Model Six and the Royal 400 models.

have a good look inside

https://www.ebay.com/itm/154513478054

loose

https://www.ebay.com/itm/254646609730?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc...

I have not come across all specs of the 18WS, but these are genuine IMO.

Royal 400 Specs: 8 ohm impedance, 4lb-10 oz ceramic magnet, which is why it appears so small, compared to my 15W's physically larger Alnico type magnet at 5-1/4 lb.

DC resistance of my 16 ohm 15W is 11.6 ohms; the 16 ohm 15Wk (klipsch baffle version) DC resistance is 3.2 ohms, 

https://products.electrovoice.com/binary/15W,%2015BW,%2015WK,%2015BWK%20EDS.pdf

then, when buying replacement 15W, I will need a DC reading to verify it is not the K version. Seems they simply stamped the label with a lower case k, and who knows who has replaced a voice coil???

I'm gonna measure my spares someday.
       No one is going to have OEM/EV Sentry III reconing kits, except EV  or an authorized EV warranty center..

        Anyone else would be proffering aftermarket, junk parts.    I'd never consider that an option!

        I'm in the neighborhood of 685 Miles, from Plainfield, NJ.

              "...who knows who has replaced a voice coil???"

      Back in the day: we reconers were buying our parts from Waldom Electronics*.     All of their voice coils were wound with round, copper wire and they carried parts to recone virtually anything commonly manufactured.

       If their catalog/parts list didn't have an exact reference, via the speaker's ID numbers: they could be sized and estimated, to fit and function.
         
       In either case: very seldom exactly to original specs or T/S parameters.


       At the VC and cone junction: EV always used epoxy, which can't be dissolved, chemically.    That would require a reconer to replace everything, to change the VC, which should be easy to spot.    If you're familiar with the original EV components, that is.

           Old as the systems/components you mention are: anything's possible!

        *That's: IF a customer wanted to go the cheap route and not buy an OEM reconing kit, from the likes of JBL, Cetec GAUSS, Altec, etc, which COULD get pricey.