I like mini power amplifier less 100W because it is low cost nad easy to make project. The 65W Amplifier Class AB,I use main part electronics are IC LF351 and thansisror two part TIP3055 and TIP2955. The LF351 is a low cost high speed JFET input operational amplifier.
The TIP3055 and TIP2955 are small size but have high power. This is circuit want Voltage supply +38V and -38V at current 3A min. Have output power 65W to 75W at 8ohm speakers.