High end Class D amps?

Actually, you do not want any conductive material at all for a transformer bolt.  Even a brass or non magnetic stainless steel bolt will degrade the sound compared to no bolt or plastic bolt.  You want nothing conductive above, below or in the middle of a toroid.  Again, mount the toroid off the chassis on wood and use glue and tie wraps or wooden plate on top with plastic nut and bolt.  Likewise shielding a toroid with copper, etc. will close down the sound.  If you want to shield then do it a couple of inches away from the toroid......let the toroid radiate its field.  I also do not generally like shielded wires.

Huge thread...can’t read it all.  Not sure if the AVM Evolution A5.2 was mentioned.  Incredible integrated with tube input stage for $6500 and has optional phono-stage and DAC cards.  185w of awesome power.

I hope the Rogues were mentioned, Sphinx and Pharaoh integrated amps along with the Hydra and DragoN power amps.  

Would love to hear the AGD amps, any news on his active speaker collaboration? Cheers

Having owned the lot from Merrill to Nord to Rowland to every conceivable output board in multiple iterations, including Bruno's latest which to me sounded very similar to Ncore, tube input stages, transformer coupled input stages, etc etc..the best I achieved was with a Rogue Medusa with a ton of money thrown at it in part upgrades and it still could not quite match the best A/B amps and certainly not the best class A amps.  I concluded class D was very very good with attractive attributes when well implemented and for me best used as my summer amp or in an AV setup. I am still a fan but thought it to be limited.

Then out of curiosity this spring I grabbed an ARC DS225 from a few years back to use as a back-up in an office system backing up Valvet A4e monos at the time in the summer months. To my surprise, DS225 is easily the best class D amp I have owned and I would say on par with a top shelf A/B design of similar power. Not particularly sure why it should be other than perhaps a completely in house design by a company known for its tube products, ARC apparently spent 2 years designing its own output stage, a huge linear PS (which has also been a component of other class D designs I have owned and certainly all of the better ones). Where it differs from all others is having no global NFB and hence a more modest damping factor of 167. Sonically, its the first class D amp I have encountered that really suffers no dead zone, and is fully "on song" at the lowest of volumes. I would say its easily the most enjoyable amp I have ever owned listening to at low volumes, which I do a lot of at night. Bass which unlike most people I find typically to NOT be a strength of most class D because it is almost always over damped for the modern speaker, is stellar on the DS225, fast and articulate but with some body like bass actually sounds. The biggest difference though and where all others I have owned really fall short including the Rogue, it actually digs deep in the midrange to flesh out with some tone and grunge to acoustic and electric guitar for example, like good class A and even dare I say a good valve amp is know to do. My sense is the DS225 probably does not measure as "pristine" spec wise as say an off the shelf Ncore module, but that says more about the Ncore than anything. Grab one if you see one, somehow they fell through the audio crack into oblivion and no one really noticed. It happens. 

Bass which unlike most people I find typically to NOT be a strength of most class D because it is almost always over damped for the modern speaker, is stellar on the DS225, fast and articulate but with some body like bass actually sounds.

@petland any damping factor over about 20 or so is going to be too much for almost any speaker made. You won't be able to hear a difference between 100 or 1000 if that were the only variable....