Damping Factor vs speaker sensitivity

There is inductor resistance, voice coil resistance, resistors, capacitor impedance, inductor impedance. Your real damping factor is never anywhere near 4000.

Damping factor is pretty much meaningless unless one is talking about a tube amp with extremely low damping factor, like around 4 or less.  Beyond 8, the numbers don’t really matter that much unless the speakers have a really low impedance.  

theaudioamp, I have already seen >900 DF on a Hegel publication. Looks like they changed the way they measure it?

mike_in_nc, May be a greater smoothness give the impression that the high frequency did not sparkle as it is suppose to be, for my taste ?

A high damping factor (DF) is indicative of two things

The amplifier has a low output impedance (Which is inversely related to DF).
Generous application of negative feedback (NFB).

I have yet to come across a reasonable explanation as to why a DF of > than 40-50 or so offers any meaningful sonic benefit. I agree with the comments/perspective of @larryi above.

Charles