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Class A amplifier

Funny thing is, it’s not even the right question!
But... you're not saying it's a stupid question, are you? ;)

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As are pretty much all solid-state amplifiers regardless of class. The only thing Class A gives over AB or D is help with the winter heating.

S.
Mine has plateau biasing so it doesn't even do that. You have to really rag it for ages it before it starts to get properly warm.
 
I have been a long term proponent of class A amps, I still own one, its in the basement gathering dust. If I where to go for very high sensitivity horn speaker, I would consider using them again. Otherwise you are favoring linearity at the expense of intermodulation distortion. I have tried all classes of amplification. My advice: Get the best high power class AB amplifier you can afford (avoid mosfet amps).
What is wrong with mosfet amps?
 
20watt Class A Luxman has more in AB , 40watt or something like that , still too weak for Magico A5. How do I know? I have speakers that are 90db/2,8V two dB more than Magigo and I have played with amps that are 15W class A, and one at 30W in A and 60W in AB , that was barely enough. Now I am happy with a watt delivery of 45A/102AB. I cannot say that Class A sounds much different than AB. Maybe my Next amp will be a AB or D. Or I might just live with my class A forever..
 
What is wrong with mosfet amps?
Well, in non technical terms, they don't sound very good. Some are quite acceptable for mid-fi systems. You will not find any high end or near state of the art amplifiers (Krell, Parasound, Mark Levinson Classé, Audio Research ect.) with mosfet output stage.
 
Well, in non technical terms, they don't sound very good. Some are quite acceptable for mid-fi systems. You will not find any high end or near state of the art amplifiers (Krell, Parasound, Mark Levinson Classé, Audio Research ect.) with mosfet output stage.
All the amps mentioned are overpriced audiophile crap. I wouldn't trade any of them for anything I have including Pioneer Class A amps and a stack of Mosfet output stage amps.

We seem to be getting a bunch of audiophile troll infiltrators here.

Correctly designed and built amps don't sound. They try to be a straight wire with gain and these days many succeed. Talking about the "sound" of amps is like talking about the "good tone" of the old MagnaVox console in the early fifties.
 
Well, in non technical terms, they don't sound very good. Some are quite acceptable for mid-fi systems. You will not find any high end or near state of the art amplifiers (Krell, Parasound, Mark Levinson Classé, Audio Research ect.) with mosfet output stage.
Let's seem some legit testing to back this up. A well designed amp whether tubes or JFET of MOSFET or whatever is going to be transparent. Until someone can show that they can hear a difference all the claims of this amp sounds like this or that is just biased and sighted subjective opinion without any value.
 
We seem to be getting a bunch of audiophile troll infiltrators here.
Bring a big budget and watch them circle the victim like a committee of voulchers. Spewing all kinds of audiophile prose to impress the unsuspecting buyer.
 
Let's seem some legit testing to back this up. A well designed amp whether tubes or JFET of MOSFET or whatever is going to be transparent. Until someone can show that they can hear a difference all the claims of this amp sounds like this or that is just biased and sighted subjective opinion without any value.
Unfortunately Ammir does not test this type of equipment: you are implying that all well designed amps sound the same under all circumstances. If none of the best and acclaimed circuit designers use MOSFET output stage, does not that tell you something? How many amps do you own or have you owned? If I tell you that a Ferrari is a better car than a Chevrolet, is that subjective bullshit of no value? do I need to provide testing backup?
 
Unfortunately Ammir does not test this type of equipment: you are implying that all well designed amps sound the same under all circumstances. If none of the best and acclaimed circuit designers use MOSFET output stage, does not that tell you something? How many amps do you own or have you owned? If I tell you that a Ferrari is a better car than a Chevrolet, is that subjective bullshit of no value? do I need to provide testing backup?
There is plenty of objective data about Ferrari and Chevrolet performance. I have owned and built many amps including MOSFET as well as done blind ABX testing of amps so I have some perspective. The main reason MOSFET are not popular for audio applications is that they produce less power at the same rail voltage so manufacturers shied away from them and so development stopped (MOSFET's moved to high speed switching rather than audio applications). None the less a good MOSFET design is going to be transparent compared to other well designed amps using other technologies. If you have objective data that says otherwise I am open to changing my mind.
 
There is plenty of objective data about Ferrari and Chevrolet performance. I have owned and built many amps including MOSFET as well as done blind ABX testing of amps so I have some perspective. The main reason MOSFET are not popular for audio applications is that they produce less power at the same rail voltage so manufacturers shied away from them and so development stopped (MOSFET's moved to high speed switching rather than audio applications). None the less a good MOSFET design is going to be transparent compared to other well designed amps using other technologies. If you have objective data that says otherwise I am open to changing my mind.
I have also built tested and lived with some very good MOSFET amplifiers notably Hafler and an excellent Belgian amp kit by Velleman, simply not in the same category as the ones I mentioned. I have stated my opinion from my experience, most High end dealers will agree.
 
If I was a high end dealer I would agree as well. :)

I used to think I could hear differences between amps but then I went to the trouble to do level matched blind testing and all the differeces disappeared... it was a very interesting and surprising experience.

I had a Haffler DH-500... quite a powerful amp for its time... I was always kind of afraid of it though it never had any issues.
 
Unfortunately Ammir does not test this type of equipment: you are implying that all well designed amps sound the same under all circumstances. If none of the best and acclaimed circuit designers use MOSFET output stage, does not that tell you something? How many amps do you own or have you owned? If I tell you that a Ferrari is a better car than a Chevrolet, is that subjective bullshit of no value? do I need to provide testing backup?
You choosing who the Ferrari is and who the Chevrolet is without scientific measurements / method - highly subjective.
From science' POV, none of the brands you posted (10k$ amps) come close to a 3k$ class D amp from Benchmark (AHB2). Read the measurements and compare.
The way I see it:
Ferrari = Benchmark AHB2 (class D) and the amps that measure well
Chevrolet = audiophile BS that doesn't even have clear measurements posted by manufacturer

Back to the thread:
@rman9 IMO your system is fine. Enjoy the music and apply room correction if you can. No need for new stuff other then room correction IMO. (I agree with @Galliardist )
 
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I have stated my opinion from my experience, most High end dealers will agree.

You sound like the kind of customer they would look forward to building a long and profitable relationship with.
 
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