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Class A into Class AB

What is the goal of a designer who makes intergrated amps that have class A for x amount of watts before it goes into class AB? Are there any examples of this being implemented well? I get this feeling that it’s kind of just a marketing thing...where people think they are getting some quality class A without the very high price tag. I was particularly looking at the CODA CSiB amps where you have three choices of how much of your first watts are class A. I have since found a few other respectable brands that implement this as well. I have yet to come across anyone who has heard much of difference between AB amps and one’s that’s state "first X amount of watts..." Class A/AB. Anyone have any experience with these kind of integrated amplifiers? Just looking for a little bit of understanding as I’m trying to upgrade my amplifier.
tmac1700
chorus
976 posts
 
A for the first few and a/b after that saves electricity, heat, and money in your pocket.  You want some A to start with for the improved sound.
So no it is not a scam or marketing hype but actually giving people what they want or should want.
cat_doorman
237 posts
 
My (limited) understanding is that class B designates a push/pull configuration with each device (tube, transistor) handling one half cycle. During the transition between devices there is distortion. Class A is always on, drawing the same amount of power regardless of the input signal. Biasing the devices for class A/B helps reduce the transition distortion because there is no longer an abrupt transition between devices. Both devices operate in the transitional region which varies widely between designs. 
sf82
10 posts
 
@deadhead1000
The 590s are also A/AB. Goes up to approx 90W in AB, so there's your headroom.Fantastic amp, I have the AX, but not just class A
On the other hand, this probably shows that it's difficult to notice it moving from A to A/B

fuzztone's avatar
fuzztone
5,518 posts
 
Why you just picking on integrates?
mozartfan
2,143 posts
 
tom68971,405 posts10-09-2021 1:14amTo me the first few watts of class A are the most important. That is where 85%+ of your listening will exist
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La Creame de la creame.
Great Britain calls it  Double  Cream*  When fresh cows milk settles, the  top layer of the cream layer. = Double cream. 

With 92 db sens wide band, only 5% of the Defy's 100 watts are needeed.
Class A, class A/B is  not important. 
At 5% , Class is irrelevant.
I listen at very moderate SPL levels, maybe 75 db tops.
Even though low SPL and very near field, I still want higher sens speakers. 
Doing it all over again, I would  have a  much smaller amplifier.  with exact same results. 
IMHO 40 true watts,,make that ~~30~~~ true watts is  really more than enough power. 

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