I read your first two posts in the first thread. That does not sound bad at all already. The kit I built is not useable in the original form. I had to put in a cathode follower to make it usable.Not only kits, but apparently "complete" products coming from China require minor or major rework. You can find what I did for two tube amps here:
http://www.diyaudio.com/forums/tubes-valves/208987-yaqin-mc-100b-powerful-advertised-value.html
http://www.diyaudio.com/forums/tubes-valves/255409-lian-845-set-kit-commercial-product.html
You talked about the SRPP driving 1Mohm. I can see the reason if it is driving the power tube. this is the same reason why the cathode follower I added actually make the kit amp that is ready to go to the garbage can to at least usable. When the grid of the power tube approach 0V or going +ve, it draws grid current and totally distorts the input waveform of the driver if it doesn't have a low impedance drive. I reduced the THD by half adding the cathode follower. Cathode follower is just the primitive way of SRPP, idea of both are to provide low impedance drive. Of cause SRPP gives higher gain.
These kind of problem and over rated power is common in SS amp even by big manufacturers. I studied a lot of SS schematics, even amps from Yamaha, Onkyo and the like push also. SS amp might be able to give out rated power.....BUT how long can it last? You see 100W amp with one pair of output transistor mounting on small internal heatsink!!!! I wonder how long it takes to burn the amp if you really push it.
Even if it does not burn, THD will get really bad because the output transistors go into beta droop long before.
Thanks
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