Class A has two modes of execution, A1 and A2. In A1 the output devices conduct all the time and there is no current flowing in the grid circuit (we are talking tubes here). In class A2 the output devices also conduct all the time but there is grid current flowing during part of the cycle. For the latter there are design considerations required to prevent distortion due to driver circuit issues.
Rleff, our amps are A2. 'Pure class A' has no engineering or technical significance (although it may have marketing significance); IOW an amplifier is 'pure class A' whether it is class A1 or A2.
It does not matter if an amplifier is single-ended or push-pull, it can be class A1 or A2 in any of those embodiments.
Rleff, our amps are A2. 'Pure class A' has no engineering or technical significance (although it may have marketing significance); IOW an amplifier is 'pure class A' whether it is class A1 or A2.
It does not matter if an amplifier is single-ended or push-pull, it can be class A1 or A2 in any of those embodiments.