Well, I installed a slo-blo 4 amp fuse on SR advice as a 3 amp may blow too easily. It removed an upper end brightness as well as tightened the imaging bass and brought out more detail, more music. Then I plugged the whole system into a black SR duplex (free fuse with the duplex-a win win situation)
The amp does not use the ultralinear center transformer tap. I don’t know what Grover does exactly but it changes the amp from slow to fast, deep and powerful. He installs a storage cap which runs diagonally nearly the length of the amp underneath. He installs solid state rectification but keeps the tube for soft turn-on purposes. The 7199 tube is really a great input tube and some modern designs use 12ax7s instead. To get the fabulous dimension, dynamics and tonal richness I have mullard el34s. You could phone Grover for advice on the design. He’s behind in making cables so he can’t do any mods right now. I have another amp waiting to be modded for over a year. Of course I am using his tremendous bargain Empress cables throughout my systems.
