CLASS A POWER RATINGS
In well designed SS class A power amps I was told that although power could increase to double in class AB mode from speaker demands of 8 ohms to 4 ohms, class A suffered to be cut in half.
For example a class A denominated amp rated at 50 watts class A into 8 ohms would double to 100 watts class AB into a 4 ohm load but only have 25 watts of class A power before switching to class AB.
But I've noticed of late claims of manufacturers stating their amps double their class A power as impedance demands are halved.
So is the explanation that technology has advanced ?
@rost The confusing bit here is that any amplifier that goes to 'AB mode' is a class AB amplifier and is not class A. By definition. If you are conflating a class AB amplifier with a real class A amplifier, I can see why the question. The technology hasn't advanced in this regard. When a class A amp can double its power into half the load impedance, its simply because its built to be able to do that. The technology to do that has been around for decades. |
I like what @atmasphere said. i'll add that the heat generated by the "AB amps that operate in class A until X wpc" is never enough to convince me that they are truly operating in "Class A mode". My tube amps, class A, all the way. Jerry |
Real Class A or not, this is the Class A amp I wanted to get (never say never). I had 2 lower powered amps in the same lineup, and they were great. Krell KSA-i400 40th-Anniversary Reference Stereo Power Amplifier (hifiheaven.net) Read the specs on it and how it operates in 'Class A'. |
While I do not understand their magic, this guy does all class A only, I believe his theory is, "if the first watt sucks, why continue". His go up and down from 8ohm to 4ohm, in either direction. All I know is, the stuff sounds pretty awesome. While I don't go to magic shows, their stuff is pretty magical. |
