It's 8-16 ohm, at least on mine.
I have the Eminence 6.5" version of that speaker in a cabinet I built from an outdoor speaker I bought at a thrift store. I use it sometimes with my Hotone Nano heads but not with the Monoprice.
Hmmm, I don't think the 4 ohm Emi will work.
How's the 6.5 version sound?
@PhredE ... what's a whole step between friends.