Oh yeah, that lovely blue glow is part of the joy!
When I start up my Stereomour with the lights low the blue glow starts deep inside the tube between the zig-zag cathode and the plate. As the tube warms the glow progresses to the top of the glass and then starts it's way down the glass. When it reaches the shoulder the music starts.
It's part of the whole ritual, watching the progression of the blue glow -
