Still need to bias the circuit.
A class AB amplifier is a combination of a class B and a class A amp. It has amplifying characteristics of a class A while retaining the power consumption levels of a class B.
This particular configuration is also known as a Push-Pull amp due the NPN and PNP transistors handling half the wave.
This circuit does have a drawback in that there is some crossover distortion when the two amplified wave are added. Proper biasing should eliminate most of this, but more circuitry is needed to completely eliminate it.
