As before, you identify a peak in the harmonic distortion @400Hz with a resonance. We cannot discuss a topic like that, having that strange concoction of terms in bended meanings.
The peak could be a consequence of something moving other than the speaker cone. Since 2nd and 3rd harmonic show roughly the same amplitude measured in percentage, and additionlly there is no dip in the frequency response to explain it, we may assume there is something rattling. And such could be in the driver itself, or in the construction of the cabinet, or at the interface between cabinet and driver. In the end it's all speculation.
I strongly suggest to (a) discuss this in the DIY section, because there are people with experience and means to cross-check results directly, and (b) following that, to address the topic systematically in isolating effects. To ask for confirmation of an anecdotal observation, calling for ABX to give it the credit of science, isn't quite fair.
Sorry, can't participate further here.
(Btw, I wonder why you mention a 20y old post in another forum on that same (?) speaker, and nothing happend since then. I mean, further investigations, cross checks, in case wider usage of the technology and so forth.).
