[I was going to add this as an edit to another post, but I think it deserves it's own post.] I'm going to expand a bit on an earlier thought about why we have not seen a lot of amplifiers like this, despite knowledge of how to achieve this performance level being public domain for decades. There is a potentially significant issue for manufacturers, and that is the "commoditization" problem, the death of their entire industry, and ruin of a significant part of this hobby--amplifiers.
DACs were ruined once when the jitter problem was solved in the early 2000s, came back due to streaming, but are essentially ruined again. There is hardly any point in designing or selling one for more than $100 since for $100 you can get something that measures almost perfectly six ways from Sunday in dynamic tests, static tests, you name it. Not everyone realizes it yet, but they will soon enough. As an audiophile item, DACs are living on borrowed time.
Amplifiers have avoided dying as an audiophile product. But what if, 30 years ago, manufacturers started selling straight wires with gain (which they all could have)? With very little fanfare, one of these things actually was designed and stuffed into a PA amplifier in about 1996. Well under .01% THD at any frequency at any power level up to 500W. And I think it cost about $900. That's basically "solved". No one followed. Why not? Partially, fear of the 80s, where amps were "solved" but really weren't since the measurements weren't good enough. But more importantly, if everyone follows, and everything measures below any possible level of audible consequence, the amplifier becomes little more than a blender or a box fan, and they've all gone and put themselves out of business. Benchmark repeated the low distortion performance and added a switching supply to get the noise out, and once again, no one followed. It took decades for Krell or any "boutique" manufacturer to do this, but they finally are. Linn, Krell, and EMM Labs amps all recently measured by Stereophile show distortion levels from 20Hz to 20kHz that aren't ridiculously bad (read: 1978 levels). Very little of any likely audible consequence in any of them. How long can they all sell the same product? What if they all really did sound different before because they were all purposefully imperfect? And now Topping is selling perfection, outside of power levels, for $300. But, the B200 solves some of the power issues for $600. I suspect with a stereo chassis they could solve all of them for about $2000.
What if, say, perhaps not Topping but Parasound, Rotel, or NAD break their adherence to decades old designs and go and sell a 400wpc amp for $2500? Hypex couldn't do it with Class D (so far) since the problems (as they've admitted) are more difficult to solve there, and the elusive "flat line from 20Hz to 20kHz" is more difficult to achieve. But they're getting there. But this thing is just straight lines. No sane person could claim there is anything measured even possibly of consequence. It's a wire with gain. Now, I'll never put it past many audiophile to come up with wild levels of faith and superstition, but at some point, the jig is up. The subjectivists and objectivists have always had at least some deviations in the measurements to fall back on--"well, I can hear that" (you can't, but whatever). But if you throw every measurement in the book at something and it never does anything except perfectly amplify what you stuck in the input jacks, they've gone and screwed themselves. You can't improve or innovate on perfect. I mean, what can Topping do to follow up on this short of adding more power or meters or some other triviality? Nothing. They can sell one to everyone who wants one, and so long as it doesn't break, that's it.
This is not just a potential end game amplifier for some, but if this performance level were adopted industry-wide, it could the end of the whole game. Will the industry ever do it, and cause the death of the hero amp? We'll see.
