The best from any 'class' can be very good, indeed. Compare the best WITH the best.
A poor implimentation of class 'A' sounds no better than a mediocre version of A/B.
And I'd add that 2 manufacturers making the SAME amp from the same schematic won't necessarily sound alike or perform alike, either. Parts AIN'T parts. And every part matters from the circuit board (Glass Epoxy might be best) to Resistors (thin film not carbon) all the way to transistors and capacitors.
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