In reply to:
Maybe someone else will chime in, but those curves are generated with a sweep generator with a constant power output. Thus, the driver effeciency would be shown in the curve.
No Rat, you are correct. I'm not sure where i was going with that thought from this morning. I may have been thinking about impedance across the spectrum as it varies across drivers but the SPL measured at each frequency is still the measurement across the same.
Regardless, there are other speakers out there with more flat frequency responses. Note that hump in the 1.5-3kHz range for the M80 v2. Perhaps the brightness people are perceiving? It reads about right.
Now take a look at the Energy Connoisseur C9 response. I didn't like the sound of this speaker at all and found its tweeter to be very harsh. Tonally it should be different from the M80s around the 2kHz and 5kHz range (in general) based on these graphs. Considering the similarities i noticed between the Energy and Axiom speakers for being harsh or bright, respectively, this is obviously an influential area of the spectrum which my ears are sensitive to variations .
