High end Class D amps?


Just an observation and a question. Are there 'high end' Class D amps out there that are just as good as Class A, A/B amps? I realize that's a sensitive question to some and I mean no disrespect---but whenever I see others' hifi systems on social media, all of the amps are A or A/B. There's always Pass, McIntosh, Moon, Luxman, Accuphase, etc. Where are the Class Ds? For folks out there that want more power for less efficient speakers and can't afford the uber expensive Class As, A/Bs, what is there to choose from that's close to those brands? Thanks
bluorion
As I keep saying.....everything makes a difference. There is no Class D sound. For instance.....every amp that uses the Purifi modules will sound different from each other. It is not just whether the power supply is linear or switching.....for a great switcher will beat a not so great linear. Every single thing has to be tweaked to the max. The input stages, the regulators, the wire, the connectors, the jacks, the fuses, all has a sound.

By the way, if you are using a toroidal transformer and you use metal plates or bolts to secure it to the chassis....you are closing down the sound. You want your toroidal transformer off the chassis on a piece of wood an mounted using tie wraps and glue or a wooden plate on top and teflon screws......way better sound.

Here is something really important: All Class D amps use a filter on the output to filter the around 500K switching frequency. Without this series coil and shunt capacitor your speaker would fry. It is common knowledge that you would never want your mids and highs in a speaker to go through a ferrite core coil. (Most speaker crossovers use coils, caps and resistors.......for coils the choice is either ferrite core or air core). No high end loudspeaker uses a ferrite core coil in the mids or highs......bass....yes.....everywhere else it degrades the sound noticeably.....

So, why is it that all class D amps use a ferrite core coil on the output of their amps? Why would you want to mess up the sound with a ferrite core coil? You won’t if you value sonics. However, class D was made to be small and efficient and an air coil coil would be too large, and too expensive and possibly radiate more rf.......so, they are never used.......except for NOW. On the mods I do to the Purifi module I change the stock ferrite core coil to a custom made 12 gauge OFC copper coil. This sounds way more open and real then the stock coil......this is a breakthrough. You see, every class d amp that any of you has ever listened to has a ferrite core coil on the output. By the way, only the best air core coil will beat the stock coil. You have to listen and test and listen and test. I also use better sounding caps to ground on the output of the coil and orient these caps so that their outside foil is towards ground, for best sound. I also bypass the output stage power supply with my modified Wima caps for faster and cleaner sound. These caps are also oriented for best sound.

No class D module is "pure" or has not sound. All are compromised. No class A amp is "pure" or has not sound. You start with the best circuit....and tweak it to the max. This is how you get great sound. Using regular integrated circuit op amps on the front end will not get you the best sound. I even modify the discrete circuits and regulators I use. This game in infinite. What is best today is tomorrows boat anchor. What I try to do is create products that are so good for the money......you can use them for years without finding a boat to mount it on.

I just now thought of this.  If you are building a Purifi class D amp and you want the mods I do to the output boards then I can do them for you.  I will have to figure out the price.  Call me if interested.
@ricevs - Thanks for the offer, but I think there is lots of low hanging fruit to focus on before attempting to modify the Purifi module. At some point, I might consider it. 
Marantz uses class D in all of their highest end amplifiers now. One for instance would me the Ruby integrated, another would be the PM10, etc...


What about Techics GaN based class D amps, are there others who use GaN?


Yes, but none yet "so far" that have taken the full major advantage of the 1.5mhz switching speed on offer when GaN Technology is used, that Technics does with the 188lb SE-R1 that also uses linear power supplies, input ones are regulated.

https://ibb.co/S6CFz5y

https://ibb.co/wwH0vNr

Here’s a little to read on the GaN transistor and it’s higher switching speed ability, that Technics have used.

https://www.psemi.com/newsroom/pres...fastest-switching-speeds-to-gan-class-d-audio

Cheers George