I see a pretty broad shelf of energy storage centered around 2000hz. And CSD's only show linear-distortion, nothing of harmonic or intermodulation. To say that cone resonances of a driver integrated into a crossover network would show clearly on a CSD is incorrect, especially when talking about THAT tiny CSD chart.
Non-sense. Are you even familar with the resonance perceptual research by Fryer, Toole and Olive? It outlines specific audibility of frequency vs. Q vs. relative level, and in different environments/conditions. The resonance here in the range you specify, would be not audible, or very slightly audible, at 2khz, on some small selection of material; nothing substantial. This is certainly not the end all, be all of speakers, this is a speaker within a budget.
Of course there are levels of resonances that are inaudible, but I don't think there's a 6.5" on the planet that can run up to 4khz and remain in the 'inaudible' levels.
And yet, no audible levels of resonance exist at 4khz on this speaker system, as clearly shown by the CSD chart here.
Nice way to gloss over the facts in this case - no 6.5" can crossover as high as in the 805 and NOT have significant narrowing of polar response and significant non-pistonic cone motions. And one wavelength? Don't you mean 1/4 wavelength, or at least 1/2 wavelength?
Well, first of all, virtually no speakers are perfect in regards to off axis response. 2nd, the speaker actually crosses over at about 3.1 or 3.2kHz, as shown by the measurements.
High crossover points absolutely have direct correlation to harshness when you're talking about a 2-way with a 6.5" or 7" woofer because of the fact that no 6.5" or 7" woofer can operate that high without the very issues you say should be addressed.
3.1 kHz is perfectly reasonable for many 6.5" woofers within the overall compromise set inherent within the budget range. Also, 6.5" is not the woofer size, it's the frame size. I have seen some drivers that have actual cones much smaller than the frame size leads you to believe is the case. I don't know what the actual cone diameter is on the B&W at issue.
The off axis response of the unit discussed here, is measured off axis, and the response of this speaker is very good in this regard. At 45 degres off axis, there is about a 2dB variation at crossover point as compared to on axis. At 60 degrees off axis, there is about a 2.5-3dB variation at crossover point, compared to on axis.
Bright does not equal harsh, odd harmonics and intermodulation equal harshness ... and using a woofer well outside it's band of predictable cone motion equals odd harmonics and intermodulation.
It's non-sense to argue over subjective impressions. But a flat response at listener position does make many commercial recording give a 'harsh' impression, one could say, due to the exaggerated high frequency level. What one defines as 'harsh' may vary. Perhaps you may mean break-up modes of a cone(clearly not the case with the B&W unit here), and some one else may mean the sibilant and un-natural presentation of excess treble sounds 'harsh'.
Every speaker builder I know in the industry, myself included, knows that 'harshness' comes from the woofer 95% of the time.
I would be cautious using the majority as an example FOR ANYTHING. If one is to judge the over-all skills of 99% of designers based on the performance of their resulting speakers, then most of them are clearly lacking over-all knowledge/ability, based on the poor performance that is common of off axis response and resonances of the systems.
-Chris