So, are Class A power amplifiers actually any good?

[fpitas]

If you opt for a Sugden class-A nowadays, you don't do that for rational technical reasons... Apart from house warming maybe?

Maybe nostalgia?

 

[fpitas]

So let me know when we listen to measurements. Listening a Steinway vs a Yamaha piano. Very different sound. However is the difference worth the additional price. Well if you have the legs why not…?

If your amps are that starkly different, at least one is broken.

 

[fpitas]

8 pages so far and no one has dragged up some class A triodes in push-pull amp? I mean in 1930 that was the cat's meow!

 

[voodooless]

Maybe nostalgia?

Is that a "rational technical reason"?

 

[fpitas]

Is that a "rational technical reason"?

Of course not. But house warming is best done in other ways, too.

 

[voodooless]

Of course not. But house warming is best done in other ways, too.

Yeah, usually that's best done with a party

 

[SIY]

8 pages so far and no one has dragged up some class A triodes in push-pull amp? I mean in 1930 that was the cat's meow!

Marantz 9. Fine amplifier.

 

[fpitas]

Marantz 9. Fine amplifier.

Well alright then. Although it offers ultra-linear mode as an option. Kind of lèse-maj·es·té.

 

[Philbo King]

Class A is far better than Class C for audio. (dumb electronics geek joke. Class C is used for single freq radio transmitters mostly)

 

[fpitas]

Class A is far better than Class C for audio. (dumb electronics geek joke. Class C is used for single freq radio transmitters mostly)

It's really efficient, though. Take that, class D!

 

[Piere]

Well, eh..., basically class-D is the chopped form of class-A. Isn't it?

 

[fpitas]

Well, eh..., basically class-D is the chopped form of class-A. Isn't it?

I'll have to think about that...

 

[dasdoing]

everybody knows that class-A is analog, and class-D is digital. and analog sounds better

 

[Mart68]

I wonder how many of those with opinions have actually listened to a Sugden amplifier. I have. Stunningly beautiful sound and in my little opinion very reasonably priced.

I've listened to music amplified by a Sugden a few times. They don't have much power or much ability to drive tough loads so performance tends to vary quite a bit depending on the loudspeaker and the size of the room/desired listening level. In that respect no different from a lot of amplifiers.

The amplifier doesn't create that 'Stunningly beautiful sound.' That's on the recording. All the amp can do it not mess it up.

 

[Mr. Widget]

Pass Labs has a lot of Class A amps: https://www.passlabs.com/product_tags/class-a/

Can you imagine the heat two of these 300 watt monoblocks must put out?

Martin

I must have missed this last March.

Yes, I can imagine it.
In the late 70s or early 80s I had a Threshold preamp that I took to the factory in Sacramento for a slight modification... don't remember what they did. Since I dropped off my preamp in person they agreed to turn the work around while I waited. I was already a DIY speaker guy so one of the techs took me to his house to hear his DIY speakers while they did the work on my preamp.

At his house there were a pair of massive 5' tall speakers with a bunch of prototype cast off parts from ESS. They were another Sacramento company that Nelson Pass had worked at. The amplifiers were even more remarkable than the speakers. His speakers were Tri-amped with six massive mono class A prototype amplifiers that were most likely design/test mules for the Threshold Stasis amps that had not yet been publicly introduced.

While we listened to Steely Dan through his quite good sounding speakers the heat rising from the six amps created very noticeable heat shimmer all the way to the ceiling.

 

[Descartes]

I must have missed this last March.

Yes, I can imagine it.
In the late 70s or early 80s I had a Threshold preamp that I took to the factory in Sacramento for a slight modification... don't remember what they did. Since I dropped off my preamp in person they agreed to turn the work around while I waited. I was already a DIY speaker guy so one of the techs took me to his house to hear his DIY speakers while they did the work on my preamp.

At his house there were a pair of massive 5' tall speakers with a bunch of prototype cast off parts from ESS. They were another Sacramento company that Nelson Pass had worked at. The amplifiers were even more remarkable than the speakers. His speakers were Tri-amped with six massive mono class A prototype amplifiers that were most likely design/test mules for the Threshold Stasis amps that had not yet been publicly introduced.

While we listened to Steely Dan through his quite good sounding speakers the heat rising from the six amps created very noticeable heat shimmer all the way to the ceiling.

Great for grilling a steak or warming up the house during winter!