This is an important update. After we do the long term listening test back and forth for different high tension power supply (B+), there result is clear, using ultra high frequency step up voltage power supply to generate 200V+ voltage is working, but the final sound quality is not as good as a dedicated transformer with super linear power supply.
Even with our active bias tube circle, I could still clearly find the beauty of "tube" when there is ALL linear power supply. Audio Precision test result is similar for different power supply configuration. But your ears just could tell you more truth about the sound quality.
So here is the decision. I will add a dedicated high voltage transformer and super linear power supply for all the Pulse Analog Stage Products that has tube there. So there will be no step up switching power supply there. And the only little issue here is now you need to plug-in ONE AC power and ONE 12V DC power at the same time.