1. triode-connected all KT88s, replaced all electroltyic capacitors by black gates (dual 47uF per section). See diagram .
2. bypass the coupling cap at the volumne control with a piece of wire
3. replace rest of coupling caps with MIT polystyrene caps.
4. tube complement: 12AX7, 5963, 12BH7, 12AX7, 12AX7, 5963, 12BH7, 12AX7. all 12aX7 are Amperex Holland.
5. replace selenium diode with silicon diode with 4.3K Ohm 1/2 Watt in series
6. check the node voltage according to voltage chart (from McIntosh Laboratory) Voltage Chart.
7. mc60 schematic Gerrad's schematic