Oh how I wish Class D amps ...

Mapman, if a tube amplifier is fully-differential from input to output, it will not have even-ordered harmonics- they will be canceled at every stage throughout the amplifier. The even orders show up when part of the tube amp is single-ended. With most tube amps, that is the input voltage amplifier.

So when Dob was wondering why our amps don't seem to have any 2nd order coloration, that is why. IOW, its not a universal thing that tubes inherently have that coloration! You can get transistors to do that too if you run them single-ended.

Unsound, I think he was talking about the input impedance, not the output impedance. I could be wrong, but that is the best I can make out of:

you know how low ICE impedance runs. Solid state preamps have great trouble with this.

But how could there be a solid state preamp that could not drive the low impedance that tubes or a passive can? That part does not make sense. Muralman1, I think you need to restate whatever it was that you were trying to say here.

What is very apparent and holds true to any and every concern here on AG is that someone selling Atmasphere amplifiers will attack, like wolves in a pack and with some of the most made up science heevar.

Uh Weseixas, do you have an ax to grind? Is that you grinding it? Maybe you could explain what you mean here- its hard to tell who its directed to.

Regarding the context of this thread though, Muralman1 made a comment that did not seem to make sense, and I asked him to clarify. Now Unsound and I often come down on opposite sides of a conversation, but he never attacks me and I have always respected him for that. He often challenges me- that is different and as far as I know, there is no rancor. He and I were in agreement regarding the need for clarification.

OTOH, Audiofeil is not usually one to get deep into the technical aspects of a subject, so I have to assume to that the 'made up science' part of your comment is directed at me. Do you care to explain that or is my assumption incorrect? Who is the 'wolves in a pack'?

OK. But FWIW, there should be no problem with almost any preamp, tube or transistor, driving a class D amp.

Atmasphere:
It was not directed at you and i do not have an axe to grind, just calling it as i see it, but I'm sure there are others who recognize the tone..

Regardless of the discussion, Tube amps,Soundlab speakers or special gravity defying horns, anything else brought up for discussion is dismissed by such.

Weseixas, OK- Perhaps I am experiencing some form of cognitive disorder, but I'm just not making sense of what you are saying here. What do you mean by 'others who recognize the tone' and 'dismissed by such'?

Soundlabs don't actually need all that much power, but transistor amps (including class D) have trouble making power into the impedances of the Soundlab. Its for this reason that people using transistors tend to use very high power amps with them.

For example if you have an amp with 600 watt/8 ohms, on the Soundlab the amp will make about 150 watts. IMO/IME the bar that has to be met by class D is not how they compare to traditional transistor designs but (especially on SoundLabs) how well they compare to tube amplification.

Michael_moskowich, Tim Aucremann of The Audio Beat http://www.theaudiobeat.com uses a set of MA-1s (with a set of ZEROs) with Sashas. I myself heard the Sashas on MA-1s at Paul Bolin's home. It didn't seem like the speaker was hard to drive at all! So yes, obviously our bigger amps can drive the speaker too. In fact it seems to me that with a set of M-60s and a set of ZEROs you would have plenty of power with Sashas in most rooms.

Here's an article Tim wrote about the MA-1s, scroll down and you will see the Sashas: http://www.theaudiobeat.com/blog/atma_sphere_ma1_mk31_upgrade.htm

Class D, as you can imagine, has made big inroads in the pro-audio and music world. For example Orange now has a class D bass amp that makes 500 watts. Its small and light! It can't keep up with an all-tube Peavey 400-watt bass head though. The Peavey has more punch and bottom end. Mind you we are comparing apples to oranges in a fashion, because its likely that music amps are not built to the same standards as high end stuff. But I find it interesting (and perhaps no coincidence) that the relationship I have observed between class D and tubes in general seems similar to what I have seen in the music field as well.

Mike, If you have a large room that may be true. But if your room is average size (17' x 25' or thereabouts) then I would not be so certain. FWIW, the live transmissions over FM have to be compressed to fit the dynamic range of the medium.

I share your interest in dynamic range- its one of my pet peeves that I feel plague many systems I have heard.

If you really want to hear dynamic range you can actually do better with an LP. Here's a recommendation, a bit hard to find but one of the bigger dynamic ranges on LP, Verdi's Requiem, on the old RCA Soria set. Try track 2, Dies Irae and then see if you can play it at actual lifelike levels. I have seen that LP bring many 'state of the art' systems to their knees. It was recorded about 1959 or so and most systems still have trouble with it...