Hi I am a lomg time lurker and first time poster here. I hope you accept me here. I really like this forum and I have gotten lots of valuable information. Goes without saying that if I can help some else in the future, I will. So i am finally going to build my Megatron, had the boards for several years already. I am sure this will be my THE amplifier for me. My boards are the first revision. I joust found and bought an unused, tightly mathed pair of very Nice NOS 12ax7`s, a pair of NOS NIB matched Philips ECC80 tubes. with the negative feedback i would assume the 6ca7’s are not so crucial, so I went with two quads of Electro Harmonix platinum matched 6ca7 and will see if i want tomget something better in the future. About the build, I have some leftover 2sa1968’s, 2sa1627AL and ST9360 with THT adapters. Has anyone noticed any differemce between them, which is the best choice. I have previously liked the 2sa1968 in KGSSHV. I will do the plate current mod for driver tubes. Should i also decrase the EL34 cathode resistor to 1K? Are there any downsides to that and How much does it increase bias? I am also using separate 300V PSU for the front end tubes. I cannot wait to get the parts and get building, I will build it as overkill as possible. Two more questions if you don’t mind: what is the voltage through the feedback resistors? In my opinion those are usually the most sensitive resistors when it comes to sound. Is 350V working voltage okay or does it need to be 500V? I am about to order the transformer, how much current should I specify for the secondaries for HV supply if I am going to do the 1K cathode resistor mod. Would around 350mA be good?