M Fowler

Not sure what is going on with the amp but remember the voltage in the US and EU are higher and some places way over 120v.

My house is 118 to 119.8v but many people say they have 125v. This will raise your HV to the plates so you have to drop voltage with a zener diode for HT to plates and larger value dropping resistors to get the preamp voltage lower.

But 395v to plates of a 6V6 sounds good.