This is my amp's schematic.

 

 

Q12 should be mounted on the heatsink with Q9 and Q11.

 R22,R23 are 2Watt Resistors.

For R11,R12 I used two 0.33 Ohm-2W resistors to get one 0.165 Ohm-4Watt.

I adjusted R16 so that the voltage drop on R12+R11 is 43mV with no speaker connected (and it's better to operate with the box closed and then open and measure fast before it cools).

I replaced the MJ15003/4 output transistors with toshiba 2sc5200/2sa1943.

Use BC639/640 or 2SC2240/2SA970 instead of MPSA06/56, I used these are only  for the simulation.

Last modification I added a transistor between input stage and voltage gain stage Q13 (See Douglas Self site for theory).

 

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