Positive and negative halves of the signal dealt with by different parts of the circuit, the output devices switching continually. Runs cooler, but the sound is not as pure.

an element and more are never away from

A power amplifier design in which positive and negative polarities of an audio waveform pass through separate output devices that conduct only when needed. It is difficult to eliminate all distortions created when the devices transition from one polarity to the other (crossover distortion), which has relegated this design to low quality audio and other applications of power amplification where efficiency and cost are of greatest importance.

In this amplifying process, positive and negative are dealt with separately, with the output alternating between the two. Class A generally offers lower distortion, Class B tends to generate less heat.

operation is the opposite of class A. Both output devices are never allowed to be on at the same time, or the bias is set so that current flow in a specific output device is zero when not stimulated with an input signal, i.e., the current in a specific output flows for one half cycle. Thus each output device is on for exactly one half of a complete sinusoidal signal cycle. Due to this operation, class B designs show high efficiency but poor linearity around the crossover region. This is due to the time it takes to turn one device off and the other device on, which translates into extreme crossover distortion. Thus restricting class B designs to power consumption critical applications, e.g., battery operated equipment, such as 2-way radio and other communications audio.

A more efficient type of amplifier configuration than Class A or AB in which no current flows through an output device when it is not carrying a signal. While prone to crossover distortion, Class B designs have been successfully used as amplifiers in powered subwoofers.