This 300W OCL power amplifier -i’m sorry for the blur diagram, but it should be readable- use 4 pairs of 2N3055 dan MJ3055 transistor as the main power components. This is good circuit, i’ve built this OCL (ouput capacitor-less) power amplifier circuit for my school project, and of course i use it for my home audio system.
There are will be 8 pieces of them which should be attached together on aluminium heatsink. It’s will be better if you add small fan to blow the heatsink and transistors (just like fan and heatsink for computer processor).
This amplifier requires 42V dual polarity or symmetrical power supply with minimum transformer current output at 5A. And of course, with high power output, you also need good loudspeakers to make great audio output performance.