Hey Ceej, I saw your post on the weberforum too, I agree with Lordathestrings, these are some strange numbers, I was figuring a EL34 at somewhere around 500v on the plates at 28.5 ma , Marshall must be using something different than the 1 ohm resistor method, I have heard that on some Marshalls that even the tranformer shunt method doesn't give an accurate reading, Strange, always something new to learn, Well if the amp sounds good and the tubes aren't glowing red it must be in the right ballpark and thanks for the Link.................