What amps are out there that are Class A, 50 wpc into 8 ohms?


This is NOT a buying advice question.

This is a purely theoretical question. A friend and I were trying to figure out what is available that is:

(a) Class A 

(b) 50w into 8 ohms or better

My guess is that the answers will be Pass, Sugden, and then very very expensive things like Gryphon. I'm curious to see what folks come up with.

Just for fun.

Thoughts?

128x128hilde45

Anything over 30-40 watts being sold as Class A is not pure class A, it’s class A biased.

Really???

Anything over 30-40 watts being sold as Class A is not pure class A, it’s class A biased.

This statement is misinformation. If an amplifier is class A biased, its a class A amplifier. The output power has nothing to do with it.

The trade off to a Pure Class A amp and the sound it produces is the limitation of the wattage and it's ability to drive a wide array of speakers. 

Here are some simple facts about class A operation:

Class A simply means that the output device or devices do not shut shut off at any point during the waveform to be amplified. 

A class A amplifier can be made of any power. We make one that is 500 Watts/channel (So the quote above doesn't make any sense).

The output impedance of the class A amplifier can be quite variable- depending on if the amp is tube or solid state and how much feedback is used.

On top of class A, if you are talking about tube amplifiers, there are three forms of class A: A1 in which no grid current flows, class A2 in which grid current is seen during part of the waveform, and class A3 (recently patented) in which grid current also flows.

Class A can be either single-ended or push-pull. It can be tube or solid state. Triodes and pentodes can be biased class A.

Any amplifier that is class A to a certain output power and then is in class B above that power is an AB amplifier, regardless of how 'enriched' the bias on the circuit actually is. IOW an amp that is class A to 50% of full power is an AB amplifier.

I miss my Velleman Class A K8010 Tube Monoblock Amplifiers.  They were amazing, but the heat was too much for the summer so I sold them.  I also wasn't a fan of the look.

 

Any version of the Aragon Palladium mono blocks will exceed 100 watts Class A power. The newer Iridium mono does not have a class A rating, but idle draw is 120 watts per mono block. It is probably safe to say that it is over 50 watts of Class A power.

It is probably safe to say that it is over 50 watts of Class A power.

😁 What is safe to say is that it draws 120 Watts at idle.

This is a sort of 'who cares' thing since the point at which the amp goes from class A to AB isn't important; the amp is a class AB amp regardless. What is important is how well distortion is managed by the heavy bias (that's the reason for class A in the first place).