Phase inverter noise. Probably not the tube.

[neikeel]

I’ve found some 100k pihers and used a 27k stop resistor. gives you loads of range.

 

[Matthews Guitars]

I'm taking this amp with me to the Orlando FL guitar show this coming weekend. I'll be exhibiting my replica JMP metal panels and the purple stack will be the attractor that brings people to my table.

If someone offers me enough money for a fully restored 1973 Superlead, I won't have to worry about the mod to make it run with KT66 tubes.

If I bring it back after the weekend, I'll make those component swaps.