About a few weeks ago I installed a new set of Tung Sol KT-120's in my Latino ST-120 amp and things have been nothing but perfect.
Tonight, I fired up the my stereo and I started hearing a flutter coming from my right channel.
As soon as this started happening, I looked at the amp and i noticed one of the KT120s started emitting a blue plasma color which would appear and disappear.
I quickly shut down the amp pulled the tube ( very hot compared to the other three) plugged back in thinking it may be a loose socket. Then reinstalled and tried again. No luck. I then removed the Weber Copper cap and installed a good GZ34 Rectifier tube to see if the weber went bad. No such luck. The tube started doing the same thing.
Can i assume I just experienced my first power tube failure? Is this normal for a new tube with less than 20 hours on it?
Typically will tube suppliers warranty tubes? I bough them from one of the common online stores.
Thanks for the input.