Happy TGIF! Hope everyone is ready for a relaxing weekend.
I have a question that may have been asked and answered somewhere on this forum, but I can't seem to find it or something close to it. I have a ST70 which I modded with the VTA boards from Roy up in the Evergreen State. The power supply is stock, although I did add the upgraded, recommended multi-section 80/40/30/20 electrolytic capacitor from Kevin at dynakitparts.com. I have also added the triode/pentode switch assembly from Roy, as well. It has a stock choke and power supply. The tubes I am using are all vintage stock Dynaco/Mullard. No other modifications have been made. As I recall, prior to the VTA mod, the amp was doing the same thing on initial startup. So either this is normal or something that I haven't changed/added is the problem--if, there is a problem.
My question is this. On initial startup, ALL tubes glow brightly and then dim back down as they enter their warm up phase. After the brrght glow they settle down to a faint glow. Is this normal? It seems like there is a surge of initial power on startup. What I am concerned about is the obvious: shorter tube life because of this startup surge to the tubes.
Any help from the resident gurus would be greatly appreciated, as I am relatively new to the valve arena.