This is a Class B amplifier, or push-pull follower. There is no voltage gain, but it amplifies current.
One drawback of the simple class B push-pull is crossover distortion. This example is a big improvement over the previous example.
In the last example, each half of the circuit conducts over half the waveform. In this example, each half conducts a small amount on the other half. This improves linearity (reducing crossover distortion), but it's not quite as efficient; when there is no output, it still draws current.
Next: Bistable Multivibrator (Flip-Flop)
Previous: Simple Push-Pull Follower, with Distortion
