It really doesn't make much sense to discuss amplifiers apart from the speakers with which they will be paired. Different speakers have different amplification needs, and may have been designed with certain types of amplifiers in mind, as well as being voiced with specific types of amplifiers. Some speakers will need huge wattage (not easy or cheap for Class A), and others will not. Some speakers will benefit from a very high damping factor (a strength of a Class D amp usually), but others may feel overdamped with high damping factor amps.
And I will also point you to Atma-Sphere's paper on the Power vs. Voltage Paradigms:
http://www.atma-sphere.com/Resources/Paradigms_in_Amplifier_Design.php
And I will also point you to Atma-Sphere's paper on the Power vs. Voltage Paradigms:
http://www.atma-sphere.com/Resources/Paradigms_in_Amplifier_Design.php