8 ohm Dual woofer speakers... How?

So tell me, How are the Dual Driver Speaker models actually 8 ohm impedance? Models I have owned are actually Dual woofers and are wired in Parallel so they get to a 4 ohm resistance.

However most specs say on all these models 8 ohm nominal impedance, and the newer versions I noted actually state " 8 ohm compatible" meaning what? They realize they are not really 8 ohm measured? I have actually taken an ohm meter to these speakers personally and come up with below 4 ohm somewhere around 3.8 ohm and lower on average throughout virtually all dual driver designs, I know this is not the most accurate way to get a impedance curve, but you would have to figure it needs to be at the least a 7 ohm reading to say its an 8 ohm speaker or am I missing something here?

Seems somebody needs to reveal Oz behind the curtain here.

Maybe they are 4 ohm in series or 8 ohm with a different crossover point on each driver. Just guesses.

Wire 2 4ohm speakers in series....thats how. I just ran into this hooking up bass resonators in my chairs for HT, I needed to lower the amp I was useings output so I wired 4 4ohm units in series and at 16ohms I am right where I need to be.
also 2 - 16 ohm in parallel give 8 ohm.
No I understand how to do it.. but they are not.. The drivers from many are 8 ohm each wired in parallel giving a 4 ohm but still speced at 8 is what I am saying.
What about the tweeter and midrange impedances?
Got a lot more math to do.
Crossovers can change impedance also, as well as looking at the impedance curves and where all the drivers cross...
Thats what I was getting at, So realistically the two combined in parallel is not really the impedance of a speaker than, its simply the resistance?
If it's a sealed box with a low or relatively low crossover to the mid, then the steep rise at resonance will cause the actual system resonance to be higher for the woofers than the simple 4 ohms calc'd for paralleled drivers.