I'm not yet finished building the first Blackvibe Micro but I couldn't help myself and stuffed a JCM800 into a Princeton Reverb chassis with a 1 watt 12AU7 power tube. The Master Volume Micro is full-up JCM800 to the power tube circuit. It uses a Princeton Reverb chassis, power transformer and cab. I swapped the not-so-useful pre-phase inverter master volume for a Trainwreck Type-3 post phase inverter master volume (PPIMV) so the phase inverter's gain is added to the master volume control and we have more control of how hard the tiny power tube gets hit. Please let me know if you see any errors in the schematic or layout.