Damping Factor - Interesting article

@douglas_schroeder  Yes, the difference between DF=20 and DF=2000 seems to be huge, but not for the purpose of damping.  Amplifier with DF=2000 has very low output impedance and will provide steady voltage (ideal voltage source) at all frequencies while speaker impedance vary greatly.   It will affect the sound because of that.  Damping is different story.  When we apply positive voltage speaker membrane moves forward.  When membrane moves forward on its own speaker generates also positive voltage, but now current flows from speaker to amplifier.  Opposite direction of this current produces opposite action on the membrane and membrane stops.  This current depends on back EMF produced by the speaker and impedance in the circuit/loop.  This loop contains speaker internal impedance, impedance of speaker wire and the output impedance of an amp.   Let's assume for a moment that wire is perfect.  Total resistance in the circuit will be resistive portion of the speaker impedance - most likely 6 ohm for 8 ohm speaker and resistance of the amps output.  At DF=20 total resistance in the circuit will be 6 ohm + 8/20 ohm = 6.4 ohm  while for DF=2000 it will be 6 ohm + 8/2000 ohm = 6.004 ohm.   Ratio of braking current in the circuit will be equal to ratio of total resistance - in this case difference of 6.6%.  Is it audible?  Perhaps for trained ears, but it is not as dramatic as DF=20 vs DF=2000.  There will be more sound change from less than perfect driving, than lower damping IMHO.  For DF=200 vs DF=2000 difference in damping will be 0.6%.

@douglas_schroeder I don’t question what you heard at all. My experience is none compare to yours. I merely stated, that the sound difference you heard could likely be because of less stable output voltage while driving and not because of different damping.
As I said, the difference in damping between DF=200 and DF=2000 is only 0.6% but many people believe it is 10x more. The other question is how this high DF was obtained. The easiest way to lower output impedance is to increase feedback. Adding 20dB to feedback lowers output impedance 10 times, but there are consequences of that. One of them is TIM, that produces unpleasant higher order odd harmonics, that make sound bright and unpleasant. Even Benchmark in AHB2, that doesn’t have negative feedback in normal sense (feedback is non-recursive), settled only for DF=350@20Hz. Class D might have inherently low output impedance because output Mosfets always clamp output to low impedance (either GND or VCC), but for the other classes I would even avoid amps with very high DF (like 2000). Something has to give IMHO.

Kijanki, you are a respectful member of this forum, and I thank you for that politeness. Many would become obnoxious at such an exchange, and I would cease communicating with them at that point. 

It seemed to me that you questioned the result directly when you said, "Is it audible? Perhaps for trained ears, but it is not as dramatic as DF=20 vs DF=2000. There will be more sound change from less than perfect driving, than lower damping IMHO." 

My reaction to your comment is that you feel it is quite insignificant. I am telling you that you are wrong; the difference was more on the order of swapping an amp, or as you say, sound change from less than perfect driving (which is a good analogy). 

Regarding the Benchmark products, I am somewhat familiar with the culture of the Benchmark Audio mindset, and I also go against the grain when it comes to such things as the DAC being influenced by cables, or the amp by power cords. Read my reviews of these components also at Dagogo.com 

Some audiophiles, perhaps yourself, find it difficult to accept that there are significant sonic changes in situations where they calculate that there should not be. I'm in no position to argue with you about your prodigious specification assessment, but I am in a position to tell you that if you think Benchmark's sensitivity to cables, or Gold Note's PA-1175 Damping Factor function are insignificant, you would benefit from hearing such things.  :) 

This is an important discussion. Thank Yous to the the OP and all posters responses.

I was unaware of the importance of Damping Factor as a 'factor,' in maximizing synergies between speaker and amplifier, until I started considering Cube Audio's Nenuphar speaker.

Both major reviews of the Nenuphar speaker address Damping Factor, and confirm what Erik shared in his post.

In the case of the Nenuphar, both (reviewers) Srajan Ebaen and Dawid Grzyb find low / lower damping factor pairings to be ideal / preferred.

Specifically, @erik_squires points out:

For a counter point though, look at Nelson Pass. He wrote at least one article where he showed that with some speakers, low damping factor, not high, is ideal.

Many Nenuphar owners report the same THOUGH I'm sure other factors (in addition to damping factor) are also at play.