Class A preamp or Class A amp

Thanks for your responses. As for Elizabeth, I was talking about the mode of operation. I have read that Class B or even AB has switching distortion in the transistor. In contrast, I have read that a well-built Class B can have two halves of the audio signal almost perfectly match just like it was operating in Class A.

The only class B stuff with "high end" aspirations I know of is Naim. Not my cup of tea.

Transistors need enough bias current to 'Wake them up' into their linear operating range. Higher bias levels will generate more heat and use more electricity. Since heat is the enemy of long life a cooler design may be wise.
Ron-C