Here is the 100W power audio amplifier circuit diagram build based on a pair of FET component on final amplifying process. The FET components using a pair of K134 and J49, the substitutes for these FETs are the combination of J162 and K1058. The output power will be about 100W at 8 ohms speaker. For stereo application, you should build two similar circuit.
The power supply which is used for this circuit is split / dual polarity type. This kind of circuit has three outputs that are positive, negative and ground. For stereo application, it’s better to double the power supply component (T1, C15 and C16), coz the stereo power amplifier consumes 2x energy than mono amplifier.
Then, here the PCB design for above 100W power audio amplifier circuit.