Single-Ended Triode

In a single-ended triode (SET) vacuum tube electronic amplifier the entire audio signal waveform is amplified by the power triode, in contrast to push-pull amplifiers where two output tubes work together in phase opposition. Small-signal audio and radio frequency amplifiers are single-ended by default, with the exception of balanced amplifier stages. Thus, in practice, the term single-ended triode amplifier applies only to output stages of audio power amplifiers, notably those employing directly heated triodes (abbreviated to DHT SET).
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