[curiousmuffin]

hi sorry this is not really headphone related but i have an old organ tube amp thats missing one 7868 out of four. 7868 thats byitself glows twice as bright than the other two- from having to handle twice the load im guessing. i'd like to know if its ok to run it in this state if i'm disregarding the tube life-span. im almost sure the answers no but i can still hope...

 

[tintin47]

Assuming you are correct, and they added a second tube in each circuit to decrease the usage of each tube then yes, you will see a decreased lifespan. You will probably pick up distortion at a lower level than you would otherwise, also, because the single tube is running double current duty.