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
jetter,
Also, tweak1 likes his Audio Alchemy DPA1 stereo amp, which is class D.  I agree that he may be eagerly anticipating the EVS 1200, but when he gets it his ears will tell the truth.  
 @georgehifi there are different types of audio dealers, most are not very knowledgeable I find and haven’t heard or bothered to hear a wide range of equipment, they sell whatever they have. They don’t even know about things like the importance of seismic isolation for example or their approach to this may be totally wrong and inadequate. Then there are others that are more thorough, test out different brands and only represent a few that are value for money. They also have the knowledge about setting up equipment properly and know about important aspects like seismic isolation, cabling and mains quality. I like to think we fit into the second category.

Anyhow, back on topic. The performance of class D varies enormously, there is good and bad. Even a manufacturer using the same class D modules will sound different depending on the implementation used. So just because a brand uses a Hypex NC something module, for example, doesn’t mean they will all sound the same.

And, as I have said before, just because an amp employs GaN it doesn’t mean that it will automatically sound better than other class D amplifiers that cost a lot less.
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.

Let me be clear, I like measurements. But a measurement is not inherently audible or valuable. An oscilloscope does not work 40 hours a week, and go home to listen to music. There's a big difference between a measurement and pleasure or desirability.


If there is 100kHz noise on an output, I'm not convinced it is audiuble unless I can hear it. If you go from 0.01 to 0.00001 distortion I'm not willing to pay 1000x as much for the latter.


People who cherry pick a measurement to make broad claims about the inferiority of one technology over another are not objective. They are just biased.
Quick interrupt! Here are some things you can’t measure. We have a lexicon of audiophile terms that most people understand. That’s how we communicate.

Transparency
Soundstage height
Air
Wetness
Sweetness
Presence
Beauty
Grain
Congealed

@tweak1 

By my estimate, the Icepower 1200as2 is around the $300 price per module. For the money, it's pretty good. Not so good for inefficient speakers though. All connectors on the 1200as2 are JST, using tin. I've had every single connector connected directly to the board (power/input/output), also using a high quality fuse. There was ZERO difference between direct/indirect connections. This is not a high current amplifier. My SS amp is much more dynamic and louder at a much lower volume setting. I'm afraid I agree with what Georgehifi has been trying to tell everyone (at least for lower priced class D).