Phase angle is Key. Too large a phase angle results in a lower power factor.
With some speakers having huge phase angles, you can easily turn a 100 watt amp into 30 or less. Tube amps don't like heavily reactive loads, (capacitive or inductive, don't 'member!)
That is the REAL indicator of 'easy to drive'.
If you can see the impedance and phase angle data that would help, at least from a purely technical viewpoint.
Of course, what will happen is the speaker which sounds better will also have the worst numbers. Don't buy Specs.
With some speakers having huge phase angles, you can easily turn a 100 watt amp into 30 or less. Tube amps don't like heavily reactive loads, (capacitive or inductive, don't 'member!)
That is the REAL indicator of 'easy to drive'.
If you can see the impedance and phase angle data that would help, at least from a purely technical viewpoint.
Of course, what will happen is the speaker which sounds better will also have the worst numbers. Don't buy Specs.