High end Class D amps?

Following this thread and it's very enlightening.  Too many good, thought -provoking entries to comment on.  Curious if anyone has heard or compared a new gen Rogue  Audio amp using their unique topology that deploys a tube "within" the Hypex module circuit (TubeD, tm)?  Only the Dragon and Hydra amp have this.  As D is quickly evolving, does this have merit, is it audible?

Now I can't say from many AB comparisons as I dont have access to much audiophile equipment here, but for the money I've been very impressed with a Rogue Sphinx V3.  Rogue is best known for tube offerings but also does class D.  USA made, awesome service.  It's an integrated with a true Class A pre amp section.  Not sure what your budget might be but at about $1500 it's a deal.  Uses Hypex modules in a traditional configuration.  Also, Rogue offers the Pharaho integrated with 300 wpc and "integrating a true class A pre amp within the Hypex modules".  Its a different configuration/topology but I've never heard any comments on the sonic differences.  Would love to hear from Agoners if they have any experience. 

Klh007, thanks.  Will look at those too.  Just wondering if the tube adds a real (warmth, harmonics) difference or not.  In any of these designs. The notion of rolling to tune to a preference is alluring.  I use an tube buffered R2R DAC and its a real handle to tweak with.  

As I've said, I'm no EE but the board's "wiring" or circuit path into the Sphynx's modules seems infinitely less complex than what's going on in the Dragon board's circuits going into the Dragon's  modules.  Rogue clearly describes inserting the tubes somewhere within the module path, both in their product descriptions online and in several interviews and reviews online with designer Mark Obrien (one is at Dagogo site, another is at Positive Feedback issue 60).   Just sayin.

Thanks for adding your experiences with D amps, specifically hybrids which hold my interest.  I have a Sphinx integrated now and have 2 sets of tubes on the way to roll (including the Mazdas...).  One thing I failed to mention, concerning auditions, is that I live in Anchorage AK.  There is ONE store in town that has ONE Primaluna  amp on the floor.  Seattle is over 2000 mi away.  Unless Best Buy counts!  Sure, some shipping back and forth possible but likely a few hundred $ per pop in the returned case as many vendors treat us as NOT continental USA.  Trying real hard to wittle down to a few lines/implementations.   So far as I can tell,  every line mentioned using tubes is using them as input buffers.  Only Rogue is doing (apparently) it different in their TubeD models by putting them "within" the Hypex module.  No EE here, but was wondering if thats potentially a sonic step change from their previous buffer input style models like the Sphynx/Paroah.  OK, back to the thread.

djones51:  I don't think that "insert" has to be literal!  There is a myriad of pins on those modules that likely allow for other configs.  Did you read any of the interviews provided or any others out there?  I don't have a dog in this hunt, I'm just asking if anyone has any experience in comparing Rogue's basic tube buffered input style to their TubeD designs.  As I've said, I live in an audio desert and shipping amps around gets kind of expensive quickly.

From Dagogo - MO: What is really exciting to me is that these amplifiers are much more than just a tube circuit in front of a class D circuit. We use only the modulator and mosfet output stage, and bypass all of the other circuitry on the amplifier modules we are using. We actually combine the tube and buffer stages with the output section, using proprietary circuitry that makes the output section perform like a tube stage rather than solid state. What is quite gratifying is that we have had numerous class D naysayers wind up purchasing them.

From Positive Feedback -  So I built what is a basic Hypex-type amplifier, as that was the baseline on one side; and then I guess our top-of-the-line Apollo mono-blocks were the design goal on the other side. I never started off to make a pure digital circuit; I just built one without the tubes in it—though I knew that wasn't what I ultimately wanted. But I wanted that as base line: like, okay, here's what the Hypex Modules sound like used as they were designed to be used, to build the same kind of digital amps that a half dozen other companies out there are building with the Hypex Modules, the big difference being that we only deploy the switching MOS-FETs on the output section of the modules and otherwise we bypass everything on the modules that Hypex supply that everyone else uses—we are not using the Hypex Modules' driver stages or their input stages.

Seems pretty evident to me that unless a respected and accomplished guy like M O'Brien is really being evasive, exaggerating or such, there is a decidedly different implementation of the tube portion and use of the Hypex modules, in those amps.

Lastly, I really don't care about the details and as it's been stated, likely correctly numerous times in this thread, it's all about the implementation details. This would seem to be a different implementation.  Just asking about experiences of any audible differences within the lineup, due to this implementation.

Ok so A) Sphynx is the regular tube buffered input upstream of the D module implementation and the Dragon is the TubeD, just to be clear.  B) if by looking at a picture one can determine that bypassing select functions within the D module is not happening, then maybe so.  If not, then having those differences is indeed a novel approach.  And "We use only the modulator and mosfet output stage, and bypass all of the other circuitry on the amplifier modules" would seem to merit a listen or curiosity.  After all, isnt it desirable distortions that make pure tube amps what they are anyway?