Holy Grail of D Class Amp

I moved from a Yamaha AVR, that was at the time promoted for its sound quality, to a NAD M33 class D, Purifi Eigentakt Stereo integrated.

It caused a huge improvement in SQ. So good it leaves no desire for changes.

The space, weight and energy savings of the amplifier are a huge benefit. When you have a small home and care about the environmental impact of your system. The M33 is practically always on for gaming, watching TV, background music or high quality listening. So longevity and energy saving are very important as well.
It drives the low impedance Buchardt Audio S400 Signature Edition speakers and unfolds their beauty in Sound Quality. The clean compact Danish design speakers are mounted on beautiful designed and crafted Buchart stands.

In our living room it is the right thing in the right space for the right people. The entire family loves that system.

For my home office I am saving up for class A/B Swiss made compact Rowen power stages combined with Swiss HD (Rowen drivers and cross over, or rather the lack of cross over complexity) acoustic suspension high efficient bookshelf’s. The ideal solution for a system that has to sit on a side board due to constraints in space.

I’d love the Polish made Feliks Tube headphone amp to go with my Meze cans and Pro-Ject DS Tube Box phono stage to go with my 40 years old Thorens TD105 turntable.

There are just no absolutes, and why not mix and match, rather than swear by a single concept.


There are absolutes when every Class D amp you have tried gives you a headache after listening for an hour or so at your normal listening sound level. It’s a problem when your listening sessions are almost never less than two hours long….

When you factor in the more clinical sound…well…

There is a reason that PS Audio’s top shelf amp is not Class D….


Sorry, but I have to disagree…
I listen to it everyday for at least 5-6 hrs since i am in homeoffice…
The Kula sound is so sweet, airy and full of detail that every second listening to it is just pure joy and emotion.


Congratulations! It’s a wonderful integrated amp. Enjoy!

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This is how I lean also. I do plan to audition at least one each high quality Class A, A-A/B, and D amps. Depending on results and budget I would be quite tempted to have 2 very different amps on hand to switch in and out depending on mood.

I had your earlier reply in mind when reading a Pass Labs harmonics and distortion tech article I posted. Not so much that I thought your physiological response to Class D might be related to these phenomena but because we really don’t fully comprehend all that affects the body. How or why we perceive and thereby prefer different attributes is probably one of the more fascinating aspects of this obsession. I’m thankful technology is enabling development of these very different approaches to audio reproduction but I’d be surprised if it leads to the demise of other topologies. If that were the case tubes would have been relegated to the history books.

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I agree that psychology and biometrics of each individual has a huge impact on how we perceive sound. That is why we should stop Talking about absolutes and appreciate that different people have different perceptions and preferences.


Oh that is really sad. So you get headaches at places that play music through class D amplifiers? What about in the car? Or is it only at home?

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Arguing about someone’s preferences seems silly. Some folks like escargot! Yeesh!
But after reading about and watching Steve Guttenberg and John Darko review the Mola Mola class D Kula, it’s at the top of my list for future experiments; this coming from a devoted Class A guy.


Why don’t you try to focus on what you like? Plus, you talking about your headaches is giving me a headache. You mention it in every single thread about such amps.

Look how many times you do this, homie!




I love my M1200s driving Harbeth 40.2, and have the longest listening sessions I’ve ever had.

There is an upgrade thread for M1200s to BHK300s, but I am just too pleased with my sonics (and my energy bill isn’t too scary) to even consider it. The “edginess” described in that thread, particularly in female vocals, isn’t something I’ve thought of myself…and I definitely dig female vocals. Trying to detect with Roberta Fleck’s rendition of Bridge Over Troubled Water and Marisha Wallace’s Tomorrow, and I just can’t. Listen to those anyway.

I’m not gonna say the M1200s are the holy G of class D, but they are at least lovely. Previous amp in same system was class AB McIntosh MC462.


Tons of buzz about the GaN class D Atma-Sphere monoblocks on other forums. Retail for under $6k (for pair) I believe. Haven’t heard them but intrigued. 100% home-grown design by Ralph Karsten - doesn’t use 3rd party modules like almost all other class D amps tend to.

More power to you folks that can listen to Class D amps. I pointing out that not everyone likes them or can listen to them at the same sound level they can with other amp topologies.

Music in the car is just background sound for me. It is never all that loud compared to the ambient sound level. So my car stereo amp topology does not matter.

Class D has continued to improve over the 40 plus years I have paid attention to the technology. It just isn’t there yet for me and how my body responds to the sound.

Honest question: have you heard M1200s considering your history of headaches?

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I’m gonna take that as a no. Why would you if they give you headaches? Why would you follow class D at all? I know I wouldn’t. I will digress.

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Pretty dangerous to paint “class D” with a single/broad brush, or to make sweeping generalizations about the class as a whole. It is so fast-moving that unless you’ve heard the latest and greatest amps of the last year or two, you haven’t really heard the best of class D. Each year it gets better. Designs that are 4-5 years old are ancient in this technology (like a Blackberry phone). I don’t know yet whether some of the GaN stuff is the best yet, because even before it there were some great class D amps (see Merrill audio as one example).

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I hesitate to speak for anyone, but if Class D didn’t have the potential to be great (yet), I would suspect PSA would have never touched them. But they did. And while I haven’t heard all of their Class D offerings, IMO they certainly hit the mark with the M700s. I suspect from what I read here and elsewhere that the others, especially the M1200s, are very successful, too.


I think that the worst modern Class D designs could be accused of is bleeding through their ultrasonic switching frequency, albeit at a very low level. I suppose if you believe that you have subliminal bat hearing then this could be a disadvantage. I definitely do not, and they sound fine to me.


But have you checked with your local bats to learn if they have headaches?


:slight_smile: No, but I have a stepdaughter-in-law who is an acknowledged expert on bats. I could ask her, but I dread the reply. Asking her about bats provokes a response on a par with asking an audiophile about cables.


Neat! I like bats and have numerous bat houses.

What does she do?