Some funny comments about Parasound in here—really highlights the ignorance that pervades these forums.
I have had the original A21, A21+ and JC5. All three can power any speaker to deafening volume without breaking a sweat. The 21s can output close to a kilowatt into a 2 ohm load.
I’ve also compared these to more boutique amps from the likes of Pass, Bel Canto, Luxman, and Coda. The Parasounds are not remotely out of place in their company. In fact, I prefer my original A21 to the Coda No.8 which retails for twice the money. The A21 is not perfect, but short of a $20K Boulder, I haven’t encountered an amp that is wholly better.
IME, all the Parasounds sacrifice some resolution in the top octaves relative to others, but they trade that for an effortlessness and bottom end control that is lacking in many, if not most, competitors. So like most things in audio below middle-five-figures, it’s a matter of tradeoffs.