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In analog push–pull power amplifiers the two output devices operate in [[antiphase]] (i.e. 180° apart). The two antiphase outputs are connected to the load in a way that causes the signal outputs to be added, but distortion components due to non-linearity in the output devices to be subtracted from each other; if the non-linearity of both output devices is similar, distortion is much reduced. Symmetrical push–pull circuits must cancel even order harmonics, like 2f, 4f, 6f and therefore promote odd order harmonics, like f, 3f, 5f when driven into the nonlinear range.
A push–pull amplifier produces less [[distortion]] than a single-ended one. This allows a [[Power amplifier classes#Class A|class-A]] or [[Power amplifier classes#Class AB|AB]] push–pull amplifier to have less distortion for the same power as the same devices used in single-ended configuration. Distortion can occur at
A class-B push–pull amplifier is more efficient than a class-A power amplifier because each output device amplifies only half the output waveform and is cut off during the opposite half. It can be shown that the theoretical full power efficiency (AC power in load compared to DC power consumed) of a push–pull stage is approximately 78.5%. This compares with a class-A amplifier which has efficiency of 25% if directly driving the load and no more than 50% for a transformer coupled output.<ref name=Yunik73>Maurice Yunik ''Design of Modern Transistor Circuits'', Prentice-Hall 1973 {{ISBN|0-13-201285-5}} pp. 340-353</ref> A push–pull amplifier draws little power with zero signal, compared to a class-A amplifier that draws constant power. Power dissipation in the output devices is roughly one-fifth of the output power rating of the amplifier.<ref name=Yunik73/> A class-A amplifier, by contrast, must use a device capable of dissipating several times the output power.
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