I went from Class D to Luxman A/AB - And most of what you think is wrong


Hi everyone,

As most of you know, I’m a fan of Class D. I have lived with ICEPower 250AS based amps for a couple of years. Before that I lived with a pair of Parasound A21s (for HT) and now I’m listening to a Luxman 507ux.


I have some thoughts after long term listening:
  • The tropes of Class D having particularly bad, noticeable Class D qualities are all wrong and have been for years.
  • No one has ever heard my Class D amps and gone: "Oh, wow, Class D, that’s why I hate it."
  • The Luxman is a better amp than my ICEPower modules, which are already pretty old.

I found the Class D a touch warm, powerful, noise free. Blindfolded I cannot tell them apart from the Parasound A21s which are completely linear, and run a touch warm due to high Class A operation, and VERY similar in power output.


The Luxman 507 beats them both, but no amp stands out as nasty sounding or lacking in the ability to be musical and involving.


What the Luxman 507 does better is in the midrange and ends of the spectrum. It is less dark, sweeter in the midrange, and sounds more powerful, almost "louder" in the sense of having more treble and bass. It IS a better amplifier than I had before. Imaging is about the same.


There was one significant operational difference, which others have confirmed. I don't know why this is true, but the Class D amps needed 2-4 days to warm up. The Luxman needs no time at all. I have no rational, engineering explanation for this. After leaving the ICEPower amps off for a weekend, they sounded pretty low fi. Took 2 days to come back. I can come home after work and turn the Luxman on and it sounds great from the first moment.


Please keep this in mind when evaluating.


Best,

E
erik_squires
@georgehifi, you really must go and listen to some amplifiers before giving opinions. As @ricevs says there are many factors that add up to influence the sound of an amplifier, just because it is using GaN doesn’t necessarily make it better. This was shown in a recent high end class D comparison were a GaN based amp came second despite being considerably more expensive than the “conventional” class D amp that came out on top. A close third was a class D amp that cost considerably less than the GaN based amp.

We have listened to a number of highly regarded class A/B designs and a particular class D design we use was far better.

You mentioned Soulution class A, we know somebody who has had the 7 series (£50k +) in his system and changed to the same class D amp that won the shootout mentioned and is very happy with the changeover.
you really must go and listen
I do, but sorry toetap I also go with the views of these 10 top amp designers, before listening to a retail salesman as yourself.
https://forum.audiogon.com/posts/1785554
This conversation turns a lot of my Audiogon impressions on their head. People who, I think, believe that great sound qualities can’t be measured are at the same time suggesting that because of inherent measurable design challenges of class D, that no class D amp can sound good. It also seems that more measurement-oriented folks may be coming out against class D because...I don’t know. The latest designs (NCore and purifi) seem to have dampened the IM distortion well into inaudible range. 

Nothing to do but listen to the new designs as they come out and try to get rid of our preconceptions. I have a cheap NCore design on order and I’m looking forward to possibly hearing the difference. Given that it is, effectively, a weak AM transmitter, I’m going to move it away from my sources, as that *could* be a source of problems. 
@georgehifi, I stand corrected, you are correct. For whatever reason I was under the impression that it was a class D amp. It is not. Well that's ok, but now I'm really curious about class D, George Hifi you got a loaner I can try?
Earlier, George gave a list of well respected manufactures of high end components. They all said how class D was inferior and it wasn’t as good as their stuff and yada, yada.

Did anyone stop to think that these other high-end manufacturers are purposely downplaying class D because then no one would buy their overpriced components?

People see two amplifiers in front of them. One is a class A/B that costs $40,000 and the other is a class D that costs $4,000. People will automatically assume that the $40,000 amplifier must be better because the price difference.

High-end manufacturers know people are gullible and listen with their wallets.