Why do tube amps often subjectively sound more powerful than SS ?

Just thinking out loud. Tube amps also tend to boost the mid bass and mid range (from about 1 kHz to 2 kHz or ao) due to their low damping factor interacting with speaker impedance. This could be part of the explanation for differences in ound versus solid state.

How many tube amps have a damping factor of even 10 into 8 ohms, especially with 4 ohm speakers(halving the damping factor) that are so common today? I can only think off the top of my head of one tube amp with a high damping factor, the old Melos amps that had a damping factor of 20(unpublished Atkinson test). Every published Atkinson test of a tube amp I've seen(and I've been a subscriber since before Atkinson) shows substantial frequency variance with frequency.

Then why do almost all the damping factors measured by Streophile fall below 10 and usually well below. And mor observationally why isn't the frequency response of amps shown by Stereophile into a simulated speaker load so far from flat?

Actually you don't need a degree to design tube amps. I winder if Bill Johnson had a degree. I'm lazy so I won't do the research but I'd bet a significant number of tube amps were designed by people who learned on the job. And I bet that includes a lot of well regarded tube amps. Most reviews for tube amps are positive.

Your example of open baffle speakers is a very small niche area and on top of that many open baffle speakers are designed to be used with higher damping factors.

I've used and loved tube amps. They have their pluses and minuses. In an imperfect universe like audio properly used they sound good. I'm just throwing out the idea for discussion that they may seem louder than a comparable solid state amp due to their high output impedance(low damping factor). I don't disapprove of tube amps.

Primarily to only add to the discussion. I had demonstrated to me by my friend Murray Zeligman and David Berning that full loop negative feed back was deleterious to linearity(a Berning amp with variable feedback and as the feedback was reduced to zero what I heard sounded better to me).

And just to add to things I've always wondered about more use of feed forward. If done right it wouldn't have the phase problems of feed back.