Hi,
By chance, I turned on my Kaiju in a darkened room and immediately noticed both 300B's had blue glowing rings near the tube's top (where the glass turns vertically straight up.) I've attached pictures of one of the tubes below. I did some research into this and learned that blue glows can either be benign or a sign of a bad tube that can be harmful to the amp, perhaps over time. I don't know enough to make a distinction, so would someone please look at the pictures and tell me which kind of glow this is. TIA! I actually find the blue glow pleasant looking, so hoping it is fine.
The tubes are stock, and the amp has the DC filament board. The amp has been running for about 8-10hrs a day for the pass 3 weeks. The getters are still shiny silver.
