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A/B/AB/D---Please recommend posts that introduce amplifier types.
- Thread starter DNCAgain
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- Thread Starter
- #3
I mean if there's any posts from which can learn some electronic design?
Not that hard to search amplifier classes for definitions and such....what are you concerned about?I mean if there's any posts from which can learn some electronic design?
- Thread Starter
- #5
I lack a foundational knowledge of electronics. Due to the need for brevity, the definitions on search engines contain many terms I find difficult to understand. Moreover, videos explaining these terms might be created by biased audiophiles.；（
Amp classes are largely about design decisions.. A well designed amp is fine. Class A amps will generally be thermal/consumption issues but not generally any particular advantage. Look for well measuring amps no matter the design and you'll be fine.
- Thread Starter
- #7
Actually, I often encounter the view that Class A amplifiers have the lowest distortion (because they are more "linear") and outperform Class B/AB types, despite their extremely low efficiency.
Moreover, low-cost Class D amplifiers usually underperform low-cost Class A ones due to design complexity.
I don’t quite believe it, but I can’t refute it either.：（
Why not? This site is about objective performance and Amir has comprehensive measurements of many amplifiers. If an amplifier has good measured performance, sufficient power for your application, the build quality and features that you want, then it is good enough. No need to worry about what other people say.
RexrothPigeon
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all BS
Philbo King
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Here is a decent explanation:
en.wikipedia.org
Note that classes C, E and F are used only for radio/TV signals (more generally termed as RF).
It's a bit of a rabbit hole if you don't know any electronics, but everyone starts somewhere.
Power amplifier classes - Wikipedia
Note that classes C, E and F are used only for radio/TV signals (more generally termed as RF).
It's a bit of a rabbit hole if you don't know any electronics, but everyone starts somewhere.
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It’s a bit of history and taxonomy altogether , people like to sort stuff .
It’s not a quality ordering, for non engineers it might look like that .
You can probably find designs that does not exactly falls neatly into one bucket
It’s not a quality ordering, for non engineers it might look like that .
You can probably find designs that does not exactly falls neatly into one bucket
solderdude
Grand Contributor
In simple words:
Class A gets very hot and needs to be large in order to dissipate heat.
Class AB needs to get bigger and heavier when they have to supply a lot of power. Again has to do with heat dissipation.
Switching amps can be very small, lightweight as they don't get very warm when they have to deliver power.
In general cheaper and lower power designs may not perform well (but may still sound good/decent) simply because of financial choices being made.
The time that class AB designs could sound bad or worse than class A is a long, long, long time ago. The myth however still goes around.
While cheap switching amps may work just fine they simply aren't as good in a number of aspects than more expensive switching and class AB amps.
Simply a cost decision made by the manufacturer.
Don't buy cheap crap even when people rave about it.
Don't buy overpriced stuff either which is supposed to 'sound better'.
Transducers and recordings all have a different 'sound'.
Class A gets very hot and needs to be large in order to dissipate heat.
Class AB needs to get bigger and heavier when they have to supply a lot of power. Again has to do with heat dissipation.
Switching amps can be very small, lightweight as they don't get very warm when they have to deliver power.
In general cheaper and lower power designs may not perform well (but may still sound good/decent) simply because of financial choices being made.
The time that class AB designs could sound bad or worse than class A is a long, long, long time ago. The myth however still goes around.
While cheap switching amps may work just fine they simply aren't as good in a number of aspects than more expensive switching and class AB amps.
Simply a cost decision made by the manufacturer.
Don't buy cheap crap even when people rave about it.
Don't buy overpriced stuff either which is supposed to 'sound better'.
Transducers and recordings all have a different 'sound'.
Johnkeizer
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I have owned 2 class a power amps.
Have a suspicion that the different/better sound is more due to the heavy duty power supply needed rather than the class a bias itself.
As competent class ab amps often have a couple of watts of class a bias and that is all I, and I suspect most average audio enthusiasts, use, a good ab amp is all I need.
Have a suspicion that the different/better sound is more due to the heavy duty power supply needed rather than the class a bias itself.
As competent class ab amps often have a couple of watts of class a bias and that is all I, and I suspect most average audio enthusiasts, use, a good ab amp is all I need.
- Thread Starter
- #15
Sorry but I can't have access to Wikipedia due to some restrictions and lawsHere is a decent explanation:
Power amplifier classes - Wikipedia
Note that classes C, E and F are used only for radio/TV signals (more generally termed as RF).
It's a bit of a rabbit hole if you don't know any electronics, but everyone starts somewhere.
- Thread Starter
- #16
Thanks,solderdude!
- Thread Starter
- #17
So, would adding an extra power supply to the amplifier bring any gain?
However, a popular view among audiophiles is that power cords can also make a difference, which surprises me greatly (and seems a bit ridiculous
However, a popular view among audiophiles is that power cords can also make a difference, which surprises me greatly (and seems a bit ridiculous
Johnkeizer
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I was talking about the power supply in the amplifier, ie transformer and capacitors, which for a given class a output are always larger than a similar power output class ab amp.
And no, I am not a fan of fancy and usually expensive power leads.
And no, I am not a fan of fancy and usually expensive power leads.
Like other said:
You’ll get that a lot here!
As for power supplies: they can help you get some more power out of an amp in some cases. They are no magic veil lifting devices, though.
Over designing power supplies is not a virtue in itself, it’s a typical audiophile over reaction. The opposite is true an underspecked power supply is a problem , which suddenly makes ridiculously overdesigned supplies a virtue ?
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