Mr. Panos and other friends,
Maybe you have not bothered to see these photos, this is 5.6 kw version on 1 ohm load,not 20 kw,A real practical circuit, 20 kw. version in ab class can also be made but I also know that won't be a practical amplifier, As you have mentioned lots of power supply , which won't be possible with single phase, and tons of output transistors with lots of heat sinks and fans to cool.4 nos. of these 5.6 kw. can be used in practical to give more than 20 kw., about H class and D class i know they are more efficiant , but I am a class AB lover , so I will go only with class ab.To see my works please spare some time and visit ---https://www.facebook.com/vedmitraa