The measurable difference between class A and AB is the crossover point. ie. In class A designs one tube/transistor amplifies the complete waveform. So bias current in transistor designs are at max levels all of the time. In a class B circuit, two transistors or tubes push/pull together to make the complete waveform. One does the (+) side and one does the (-) side of the waveform. That allows the bias current to be nearly zero at idle. The issue is the noise or not so perfect handoff of one transistor to the other as the waveform switches sides. One a scope, it can be seen as a discontinuity in the waveform at the zero line. Of course, todays amplifiers all but eliminate that crossover discontinuity. Older A/B amps had a brittle sound, an unpleasant edginess to my ears. I didn't like listening to them at very loud levels for long.
Actually difference between class A and AB?
Class A amp sounds like holy grail of HIFI world.
But class A amp are much heavier, more expensive and rarer than class AB or class B design. Few can afford 100 LB weight of a 2-channel 100w/c amp.
Is there any actual difference between class A and class AB when listening to actual music? And what is that difference?
But class A amp are much heavier, more expensive and rarer than class AB or class B design. Few can afford 100 LB weight of a 2-channel 100w/c amp.
Is there any actual difference between class A and class AB when listening to actual music? And what is that difference?