Class D Technology

Thank you maplegrovemusic and Kijanski,

    I'm glad you thought it was a useful post.

   I  did a lot of research on class D amps and technology before buying my 1st one about a few years ago.  Guido Corona, mapman and atmasphere   helped me a lot on this site and I really appreciated it.. I now own 3 different brands and have gained some personal experience with them over time.  

    I'm glad I have some somewhat decent knowledge to pass on to others looking for similar knowledge.as I was.  I also have learned along the way that class D is a great choice for myself and many others but not right for everyone. 

Thanks,
  Tim

      

Bel Canto Ref1000 Mk.II

The newer Bel Canto e.One Ref600M monoblocks (that had the newest Hypex modules) with Belcanto’s own designed "series" output filters, these so far have sounded the best Class-D to me, and I thought, yes I could live with this.
They were were driving a speaker that had a very benign 6-8ohm flat load tweeter with minimal -phase angle which was one of the Raven Ribbon tweeters, once we used another speaker, with not such a nice benign load in the top end my opinions of it were dashed somewhat.
http://loudspeakershop.eu/glosniki/images_dane_750/raven/linesource_imp.png
Cheers George

My D-Sonic M3-1200S 2 channel amp is a dual mono design using Pascal modules which I believe is still Dennis's module of choice. It powers my Maggie’s with ease. I can tell you, Dennis’s amp came highly recommended and I was skeptical but decided to do a trial. My McIntosh amp was quickly pulled from the rotation and put on the block, it’s that good and meshes well with my Modwright LS100 preamp.

1. They are extremely quiet, having THE HIGHEST S/N Ratio and THE WIDEST DYNAMIC RANGE of any amp type, with almost no audible background noise and highly detailed.  I can turn my volume control to maximum without any source playing, put my ear an inch from the tweeter panel of either speaker, and there is absolutely no sound. Is this possible with a class A amp?

Yes, and with tube amps too.

The reason? Your volume control setting is saying something about your preamp and sources but nothing about the amp. We make tube amps that have to be quiet on speakers that are 107 db... try putting your amps and preamp on a set of speakers like that and see how much noise you have then. Low noise is not a weakness nor advantage of class D amps.

Dynamic range isn't a particular strength or weakness either- it is the same as any good amp.

The real strengths of Class D are low cost, high efficiency (about 85%) and because of the latter, smaller size as large heatsinks are not as important. Class D was first proposed in the late 1940s and can be done with tubes. Its a fairly simple technology which is why its also inexpensive to build. **Those** are the strengths; what an individual designer brings to the table and how well its executed is going to have a big effect on how the amp sounds and performs. There is nothing inherent in the technology otherwise that make it inherently better. The reason its showing up in spades is the semiconductor industry is really wanting to make switching transistors right now instead of linear transistors, so audio manufacturers hare having a much harder time getting linear devices as easily as they did in the past and can read the writing on the wall.

If you want to demystify what class D is all about, I recommend reading this article, which really demonstrates how simple class D really is:
 https://hackaday.io/project/4369-class-d-subwoofer-amplifier-out-of-scrap

Yet you, Mr. Designer, dismiss Class D as nothing more than midfi.......