Atma-Sphere Class D… Amazing

I disagree with Ralph about tube guitar amps...they're not going away anytime soon, if ever. Note that serious pro guitar players generally start with a great tube amp in pretty much every case (exceptions for those who run "into the board" with effects...rare and generally sounding sort of processed), and add their personal pedal choices to the tube amp. Duke Levine (local Boston area guitar genius) describes his current rig in Vintage Guitar...he's touring with Bonnie Raitt...VOX AC30...I've known Duke for 20 years and every time I've either worked a show with him or simply seen him play he shows up with some of the coolest tube guitar amps on earth. Same thing with the brilliant Julian Lage...tiny 50's Fender tweeds like a Tweed Champ or some other little tube amp like a Magic. Brilliant sound...and no overdrive pedals for Julian.

I considered Ralph's D monos when I bought my Pass XA-25 but the Ralph amps (that's what they're called, right?) weren't available yet so I had no idea what they were going to cost...now I'm so disturbingly enamored with the Pass amp I'm hard to nudge away from it...I'd still like to hear the Ralphs sometime...maybe a lower powered stereo amp? Loaned to me? heh heh...

@wolf_garcia The smaller guitar amps will hang around for a while because they are low enough power that its practical to overdrive them. But the bigger stuff like 100 Watt Marshals are likely threatened, if someone can put a class D amp out there that's worth listening to. The weight is a big variable here. 

The OP has not been very clear as to whether Ralph suggested that he post his impressions. Ralph has a new product and he needs to get some attention over it. Even if not, it is pretty abundantly clear that the OP is already a fan of Atma-Sphere and is far from neutral. It is exceedingly rare for someone to go nuts over the sound of an amp. Amps have a subtle affect on overall sound, and there has never been an amp and likely will never be an amp that "bowls one over" immediately with sound from the heavens. I believe that amps are critically important to overall SQ but it takes months of living with an amp to assess it's character and attributes. So despite the silliness in this thread over non-related matters the circumspection is not surprising. 

And then we come to digital amps as a category. They are insanely cheap to manufacture as has been pointed out elsewhere in this thread. To my mind, a digital amp is a switching power supply built to drive loudspeakers. If there is a simpler way to harness power from the wall directly to the pre-recorded sound signal it has not yet been invented. Ralph has acknowledged that the box-a plain vanilla box at that-is the major parts cost of this product. When the best switching power supplies sound better than the best linear power supplies I will likewise believe that the best digital amps sound better than the best conventional Class A/Class A/B ss and tubed amps. 

Ironically enough, the discussion is still about distortion-that this digital amp has less of it. Here we go again-the old fallacy that the lack of distortion means more faithful sound reproduction. Loudspeakers are the number one producer of distortion. Distortion needs to be embraced, not made the focus of elimination. Even the power in the wall contains distortion. Harnessing raw power from the wall is not the answer. I wish Charles Hansen and Tim De Paravicini were alive to lend their voices to this discussion. I wish Nelson Pass would join. 

In summary, I have no doubt this amp sounds fine. Very fine. Just the same, it is bound to have sonic virtues and faults like any other amp. It won't make your grass greener, your hair thicker, or give you greater stamina in the bedroom. 

Also, how humans sense sound pressure does not change from individual to individual; generally, the higher ordered harmonics are used. This is really easy to demonstrate using simple test equipment. Imagine a world where every individual used entirely different hearing perceptual rules! It would be a good basis for a scifi novel 😉

@atmasphere

thanks for the reply.

Of course I am not claiming that the "how" is different in every individual. What I am claiming is that there is enough natural variation among humans in reception, processing, and interpretation of external stimuli that one can not predict with certainty how any one individual will respond, all the more so when the amp is but a piece in a complex system full of external and internal variables. Clearly experimental results with a large enough sample can yield tendencies and generalities, but again, nothing that can predict with certainty on an individual basis. From your standpoint, that’s useful. From mine, not so much as I still need to listen for myself.

I am glad to hear that the feedback from your customers has been positive. It’s clear a lot of time, energy, and thought went into your product. I won’t hold my breath waiting for the measurements- you must have your reasons for not publishing them.

It might be interesting to consider that sound itself only exists in the head of the individual. It’s a back and forth from air pressure changes to electric signals. Our ears are transducers changing the air pressure pulses to electric impulses in our head. It is in our mind that these signals are perceived as sound. A lot of links in that chain that can cause differences in how the end result is perceived.

@fsonicsmith 

Here we go again-the old fallacy that the lack of distortion means more faithful sound reproduction.

How would you define/measure faithful sound reproduction?

If the output doesn't match the input, how can the result be called faithful?