Not all watts are created equal.
Class A amplification is often described as smooth, rich, and natural. The reason is simple: the output devices never switch off. Unlike Class AB, where one half of the waveform is handled by one device and the other half by another, Class A keeps the entire signal path continuously active.
The result is freedom from crossover distortion, the subtle misalignment that occurs when handoff between devices isn’t seamless. That lack of interruption gives Class A its purity—notes flow more continuously, harmonics sound more lifelike, and the music feels less mechanical.
The tradeoff is heat and inefficiency. Running devices full-on all the time wastes power and limits output. That’s why Class A amps tend to be heavy, hot, and expensive for the wattage they deliver.
That's why a high-bias amplifier that covers the first few watts in pure class A is the ultimate topology to shoot for.
