Class A Solid State Sound

Lets not forget the difference feedback can make. 

IMHO it is nearly impossible to talk purely about the output stage class in isolation of the feedback method, if any.


Also, with so many high bias AB amps, I venture to say you listen to them mostly in their A range anyway.


3 Amps I think you should listen to, are Luxman, Ayre and Pass. I can't see you loving all of them at once. Sorry, no experience with Accuphase, however if you are the US distributor and wish to provide me with a review sample, message me. :)


Best,
E

I guess so much relates to implementation.
Both Accuphase and Luxman amplifiers enjoy excellent reputations. Accuphase employs Mosfets and toroidal transformers, while their Japanese competitor, Luxman, employs Bipolar transistors and EI transformers.  Interesting indeed!

What you will get running a Class A Pass amp into a 2 ohm load will be a very hot amp that will probably shut itself down or burn a hole through your floor. Into 4 ohms and up Pass class A amps will switch to AB at their rated power and continue on probably doubling that. God knows what the Xs 300 will do. IMHO there are very few speakers with impedance that drops below 2 ohms worth listening too. The amount of power any amp will put out is determined primarily by the size of the power supply. Whether or not the amp can safely transfer that power to the speakers depends on the capacity of the output stage and the size of the heat sinks. Power is power as far as I am concerned. I do not care about the type of output device used. It is all about topology and durability. I expect an amp like the $90,000 Xs 300 to run for a life time. If it can't I am not interested. 

Upgraded and former power supplies in my Class A monoblocks.....

https://www.usaudiomart.com/details/649314340-clayton-audio-m300-class-a-monoblock-amplifiers-custom/images/1380838/