Relatively new to the tube amp experience and so far I've enjoyed it until my AD30r cut out. To break it down it's blowing 2 fuses verified using a DMM, The HT fuse (500mA) and the mains fuse (2A), they are the correct value as stated on the chassis and I'm not going to use other fuses for obvious reasons. When turned on I get some noise out of the guitar for a very short time (during the tube warm-up period until the fuses blow, I'm using slow blows). I've only swapped the fuses once to see if the amp would blow them again the second time. From what I can tell the heater fuse must be going first and then the mains instantly after. The amp is an Orange AD30r, it uses 3 ECC83s (12ax7s) (preamp, phase inverter, reverb) and 4 EL84s and a GZ34. Here's a schematic just in case, http://www.prowessamplifiers.com/schematics/images/OrangeAD30_1.pdf I'm really hoping that this just needs a tube swap and not a trip to a tech because this thing weighs a lot.