Atmasphere.."damping factor has a basis in mythology"..
disagree. The top mega-buck solid state amplifiers all have
in common very high damping factor number's. A list of some of those amps..Soulutions 501 and 700 mono-blocs have a damping factor of 10,000. Simaudio Evolution 880-M, damping factor 2000. Simaudio Moon 400M, damping factor 800. Accuphase A-200, damping factor 1000. Parasound JC-1,
damping factor 1,200. Hegel H20, damping factor over 1000.
All class D amps have damping factors at 1000 or greater on average. The bottom line why these engineers strive to have high damping factors is the higher the number, the lower the output impedance, results in ultra low distortion coming out of the speaker. The most critical reason is the woofer. If you have a massive forty pound woofer in a 300 lb. speaker, you better make damn sure the amp you are using can grab and control that woofer with an iron fist.
Designers of high powered amps with high damping numbers and low output impedance are well aware that woofers have larger piston's that have longer back and forth travel distance since low frequency waves travel a longer distance than a midrange or tweeter wave. Having an amp with high damping and low output impedance, which is usually below 1 ohm, results in ultra low distortion and perfect piston motion in the woofer, to make certain the low end is as deep, clear and powerful as the speaker designer intended.