Class D is just Dandy!


I thought it was time we had a pro- Class D thread. There's plenty of threads about comparisons, or detractors of Class D.

That's fine, you don't have to like Class D amps, and if you don't please go participate on one of those threads.

For those of us who are very happy and excited about having musical, capable amps that we can afford to keep on 24/7 and don't require large spaces to put them in, this thread is for you.

Please share your experiences with class D amps!
erik_squires
My Hypex NCore NC400 Bridged Mono block class D power amplifiers resulted in my sound quality being more natural, clearer, having more bass, a lack of noise, excellent dynamics and details. I am running my Bricasti M1 DAC direct into the Hypex NCore power amplifers and am not using a pr-amplfier.

It is my opinion that another layer of sound is presented WITHOUT the pre-amplifier in the system (I also know some people disagree on this topic so we will agree to disagree). The Hypex NCore NC400 bridged mono block class D power amplifier is highly recommended.

Other excellent Class D amplifiers are (random order):

1) The Acoustic Imagery Atsah 1200 mono block Amplifier uses the NC1200 module and the NC1200 power supply. List price is $9,995 and the delivery time is 12 weeks (yes, I confirmed this and each unit is custom built). Acoustic Imagery reports "The ATSAH NC1200 is the NC 1200 OEM module with the SMPS 1200A700 power supply. We do not modify it in any way, it is simply as Bruno designed it. To be honest, there is no comparison, the NC1200 module is a far better amp in all departments".

2) The Bel Canto REF600 amplifier uses a the single NCore NC500 per side and is not much of an improvement over the bridged NC400 mono blocks (my opinion). Bel Canto reports "The critical issue is more how one implements any power supply. We have done extensive collaborative research with Hypex and have developed product that is as unique as the Hypex is to others in terms of their context but that ours actually sound better and are labeled Bel Canto power supplies in most cases. The Ref600M's are a recent introduction of what we have learned with the whole Black Series project”. The Bel Canto Ref600 amplifier has been in production for almost a year.   The build quality of the Ref600 looks terrific (IMHO).

3) The Merrill Veritas class D amplifier look very interesting and costs $12,000. In addition, each box is 17”wide and the two boxes are too large for my single shelf space. The Veritas amplifier is a fully Balanced design. The Veritas mono-blocks have been in production since 2011. There is an upgrade planned as well as a price increase for the new mono-blocks. It will be about 1+ year before that is released (estimated).  The reviews for the Veritas have been excellent.

4) The Mola-Mola Kaluga power amplifier also use the NC1200 module and NC1200 power supply. I was told the "Mola-Mola Kaluga amplifier is Bruno’s very best efforts and he kept a few secrets behind for himself. Every single thing has been looked at in the Kaluga’s and he is even using Kubala Sosna cabling internally. Special damping, a discrete switching power supply (which you can’t buy) and a proprietary input stage". I am sure the Kuluga sounds terrific but it is very expensive.

5)  The Jeff Rowland 525 mono block class D amplifier uses the Pascal module.  

I am sure there are other excellent Class D amplifiers on the market that I have not looked at (or discovered).  Please add additional Class D amplifiers to this list.  Thanks. 

I am considering replacing my Hypex NCore NC400 Bridged Mono Block class D Power Amplifiers with another Class D amplifier that uses the NC1200 module and NC1200 power supply. Research to date is my bridged Hypex NCore NC400 mono block amplifier (2 NC400 amps per side) sounds excellent and an upgrade to the NC1200 is expensive and maybe might only offer slightly improved sound (this is to be confirmed, some people feel the NC1200 module is the best sound).  My research continues and I am in no hurry.
Northernfox,

      Congrats on your new Bel Canto Ref600M class D mono-blocks!

      From the reviews I've been reading, good amp designs based on the newer Hypex NCore 500 module are very close to the good amp designs based on the NCore 1200 module for about half the price.  I haven't heard them yet but will make a point of auditioning them asap.  
      You're obviously already very pleased likely without complete break-in, which means they're only going to sound similar or even better going forward.

  Enjoy,
    Tim

     Class D's current state is very good and its future is looking even better.  I recently read an article about new faster switching MOSFET transistors.  

      This transistor technology is called Gallium Nitride (GaN) and is poised to uproot the high-end audio world. In fact, GaN-based Class D is much more power-efficient than traditional, MOSFET-based Class D and offers orders of magnitude better performance. Performance that to many listeners, even surpasses the quality of Class A.   At any given product price point, these new Class D solutions can meet, or surpass the quality of today's linear amplifier solutions. As an example, the eGaN FET-based Class D amplifiers can easily achieve a mid-band THD performance of 0.005%, where a comparable linear amplifier Class would achieve around 0.05%. Here's a link:

. http://audiophilereview.com/cd-dac-digital/why-well-soon-be-living-in-a-class-d-world.html

     Just to make sure everyone was aware of this important new class D development, I also posted this link on the "class D=Trash?" thread.

Later,
 Tim
Great info @noble100

I don't usually agree with the theme that "Class D is about to get as good as Class A" as I think it has been there for a while.

Linear amplifier distortion can be reduced by feedback, something digital amps may use in buckets.

Where I think the new Technics amps using this transistor will be most interesting is in amp/speaker matching, as the average Class D module is not the current delivering brute that say a giant Boulder or Krell is across the frequency spectrum. Technics has an interesting way of handling it. I handle it by making easy to drive speakers. :)


Best,

E

Gallium Nitride (GaN) and is poised to uproot the high-end audio world. In fact

Yes as I posted here, these eGaN fets are what Technics are using in their new $30k class-d and with it are able to double the frequency of the switching noise. And therefore able to remove it with low order filters more effectively from the output of the amp, without coming close to the HF audio band with those low order filters effects (phase shifts) and left over switching noise.

https://forum.audiogon.com/posts/1413469

https://forum.audiogon.com/posts/1413463


Why We’ll Soon Be Living In A Class D World
By Skip Taylor | September 17, 2016 4:27 AM

"A high-definition eGaN FET-based system with higher PWM switching frequency"

Cheers George