Pass....Accuphase....or......

+++++ Accuphase A48 great if not greatest <50W/ch SS A class amp! advantage: no maintenance needed for few decades! 

+++++ Luxman MQ-88uC lil less peak power headroom than A48, amazing dynamic range, very low noise floor for tubes, very gentle tubes use conditions to ensure long ride without replacing tubes etc.! 

@southofdallas I have A48 and P4500.. A48 is better for mid <50W peak power, very smooth/warm, P4500 is excellent for higher volume sounds <150W, rock etc.. P4500 is basically not different from A48 below 5W power.

@southofdallas "How much class-A power does the A-48 deliver before drifting into AB?"

Theoretically A48s always will be in class A mode for full power range, using resistive 8 Ohms load.. BUT, :-), speakers are not resistors, loading applied to the amp is complex / resonating load, at some frequencies much lower effective impedance than rated! For sure A48s becomes high-bias AB class amp with 4 / 2 Ohm rated speakers..

@southofdallas correct! A48 will be more stable at lower load impedance than P4600, which has higher supply voltage.

@lalitk "While the A48s is designed as a Class A amplifier under an 8-ohm resistive load” probably typo, A48 is designed as class A amp for loads = or > than 8 Ohms. for loads < 8 Ohms it is a high-bias AB class amp. 

"Class A means the output device or devices never go into cutoff.” - definition is correct!

push-pull A class amps have bias to cover max current for loads, supported by class a! if load is lower than nominal, one of devices indeed goes into cutoff!