There are very good class AB integrated amps , Boulder , Gryphons new 333,
accuphase, Luxman , if youwant class A Accuphase,and Luxman make them too
up to 100 watts into 4 hours , but they get pretty warm and suck up a ton on electricity, it’s like holding your foot down 24-7 to the gas petal . I owned a pass labs . What are your speakers ,and their sensitivity ,at what ohms is most important .