Abstract: A high-performance, distortion-free, audio push-pull amplifier has a class A driver stage that drives a class B push-pull output stage that is coupled to a load through a transformer that has a center tap primary with screen taps. The driver tube cathodes are coupled to the output tube grids. The driver tube plates are tied to the screen taps on the output transformer primary. These taps are also coupled to the output tube screen grids. At low power levels the driver stage drives the load through the output transformer. As power level rises the power stage supplies more and more of the output power. This circuit avoids notch or crossover distortion at low power levels.