I had the same thing happen to me, Here's what you need to do. Take it to a tech because it more likely has more going on with it then just the tubes going bad. This is exactly what mine did back in may. You may have some parts on the tube board that have burnt up and need replaced but if there is a problem with your output transformer like a short in the output transformer, then no matter how many times the components are replaced they'll keep on blowing. This is what happened to my TSL. Basically the exact same scenario, I tried fixing it myself, same components that I replaced kept on blowing. Took it to a tech named Deric, he fixed the same components, same components blew. He tried to blame it on my cab saying it was wired wrong, I took his word for it, got curious, went to celestion's website, and found out that it wasn't a miswired cab like he said it was. He sent the head off to have the transformer looked at and that was the culprit all along. That's not saying that this is exactly what the problem is with your amp but I remember posting a very similar thread about mine back in may. Our descriptions match up almost perfectly. There's so much going on indise this head though that saying to replace one power tube and try that first, is probably not going to work. Here's something to try though... The bias probes that come out of the back of the head behind your back grill... lay the metal grill across the 3 probes and see if the head comes to life. If so don't continue playing this way (it's bad on the other components) take it to the tech and tell him what happened. Kindly suggest the transformer get thoroughly tested.