Rel Strata 2, Is it 4 or 8 ohms?

REL Strata 2,is it 4 or 8 ohm or more? REL's can be hooked up to your Amplifiers. Yet the manual doesn't say.
What you are referring to is the impedance of the driver within the sub. But your amplifier does not see that impedance. It sees the input impedance of the sub's "high level input," which is a circuit that in turn feeds into the amplifier that is within the sub. For many REL subs, I believe including the Strata 2, that impedance is 100K (i.e., 100,000 ohms). That is a completely negligible load.

A consequence of that very high impedance is that you don't need heavy gauge speaker wire to connect your amplifier to the sub, because the high impedance will draw negligible current.

-- Al
Since REL subs are active speakers (as are most subs today), their inputs won't have an impedance similar to a passive speaker.