What does it sound like?

So what does it sound like when a tube goes? I was listening at medium to low volume levels last night, and I suddenly heard surges of static ans sound through my left channel. I also noticed that the tubes flashed and surged blue when the sound was happening. I shut down right away and everything else sounds fine after connecting another amp into the system. So is this the tubes going in this channel? Thanks for the help.
Most likely. Sometimes they surge bright red and then die. Some amps will shut down and blow a fuse when the tube goes. Most tubes give little warning of their time to go, unless they are very weak and then exhibit lower output volume in that channel. If you have acess to a tester, have them checked, or replace the tube in question immediately. Dont turn the amps back on with a bad tube, that could do more damage. Good luck with your amp.
Kehut, nice response.