Hello MaxS, power supply is 40V per rail, higher voltage possible with IRFI4020H-117P (or something like that). Output power can be easily calculated.
Project will be shared after all measurements be done.
Next 20kHz sine:
1st: input 0.2V/div*10us/div
2nd: output 10V/div*10uS/div
load: 6.5Ohm resistor.