I agree with Got Mule, and I believe that "X"factor that most of us are missing is the sheer volume that Joe gets to play at. He has been known to use his live rig in the studio quite often and that monstrosity is stadium ready! Surprisingly though, if you have ever been to a JB show you will know that he is nowhere near as loud as other acts. I was shocked that my ears did not ring afterwards and much of that comes from Joe's dedication to good tone managment. In the studio he still baffles everything and isolates the rig to keep overall volume down. That's the beauty of his gear, it's practice/gig/record ready all at a sane volume!
'67 and '74 Fender Twin Reverbs, '74 Marshall 1987 lead mkII, Metro Superlead 100. Pedals from TC Electronic, Ibanez, Dunlop, BK Butler, Electro-Harmonix, Fulltone, Maestro/Gibson, Loopmaster switching, VoodooLab, Boss. Gibson and Fender guitars, Dimarzio pickups.