You must not forget about spatial dispertion (both horizontal and vertical). Those data sheets are only infrequently made available, but they are very much responsible on how a speaker sounds in a particular environment. The M80s are particularly impressive at both.
Simpy move in front of a speaker and also go up and down while pink noise is playing. You will immediately notice a difference in tone that is both a factor of speaker dispertion and slight differences in the way your ears are facing the speaker.
