What effect does using a push-pull amplifier have on even-order harmonics?

Using a push-pull amplifier effectively eliminates even-order harmonics due to its design and operation principles. In a push-pull configuration, two transistors or tubes amplify the positive and negative halves of the audio waveform, respectively. Since each device only operates in one half of the cycle, any distortion introduced during the amplification process is typically canceled out when the two signals are combined.

Even-order harmonics, which occur at frequencies that are multiples of two (e.g., 2nd, 4th, 6th harmonics), arise from symmetrical waveform distortion. However, push-pull amplifiers promote a balanced operation that inherently cancels these distortions, thereby significantly reducing or eliminating even-order harmonics from the output. This characteristic leads to higher fidelity and better sound quality in audio applications compared to single-ended amplifiers, which are more prone to producing these types of harmonics.