actually it's "do damage TO something", but moving on..... Well, we started rehearsal and in a total "state-of-dumbass" I forgot to plug the cabinet into my 400+. I turned it on, but it was only on for about 10 seconds before I realized my error. Played and sounded just fine afterward. I think I lucked out, but is there any more concerns I should have (besides never doing that again!) Also, how long does it take a tube amp to destroy itself when running without a cabinet?