What is this thing? "Full Modulator Triode"

@viridian , Thank you!!!!  I find this subject very interesting. I appreciate your knowledge. 

Right. Your knowledge is really good too. I need to learn more Sonic exe. These knowledge really make me extremely passionate.

Josh stippich build some monoblocks using this tube back in 2003, his amps were tube rectified using mercury rectifiers. He had to use the power outlets from two hotel rooms because the breaker kept tripping at an audio show. Too bad he doesn't build tube equipment any longer, he liked to think outside the box.