High end Class D amps?

The PS Audio Stellar M1200 Monoblocks are fantastic and at a reasonable price for the pair. I am driving a pair of Magnepan 1.7i with them and the combination is excellent. I believe a eview is coming out in one of the major audio mags soon.

 In general, solid-state (ss) amps reproduce deep bass frequencies better than tube amps. A good indicator of an amp's bass reproducing ability is its Damping Factor, which basically measures its ability to control, or start and stop, the bass driver. The higher the number the better its control. Class D amps usually have much higher damping factors than the other amp types; class D amps can be rated in the low thousands, class A and AB are typically rated in the low hundreds and tube amps even lower.

There really aren't any speakers that need more than 20:1 in a damping factor and some need considerably less. On top of that, traditional solid state amps actually have enough feedback at bass frequencies to do the job (whereas they usually don't at high frequencies, which is why they are often bright and harsh).

I always thought pure class A amplification was most ideal. So why manufacture Class D amps?

Class A is all about the output section- keeping its distortion as low as possible and its quite effective. But this says nothing about the input section and driver circuitry, and the output section is still going to make some distortion (just less than if the same circuit were class AB or B).

Class D uses a different means (switching) to make power, and so does not make distortion in the same way. There are basically two means that the amp produces distortion- the first is how accurate the encoding scheme is. The second is caused by the fact that the output transistors take a finite period of time to switch on and off and so to prevent damage to them, a bit of waiting is done to allow one device to shut off before the other is turned on. Otherwise current can shoot through both devices, heating them up quickly towards failure. This waiting time is called 'dead time' and contributes to distortion. The distortion signature is different from traditional solid state and does not tend to be bright. Instead it tends to have more lower harmonics like tube amps, and not surprisingly  can sound a lot like a tube amp, except when the amplifier is overloaded.  Certainly the reduced amount of heat is an incentive- this is the main argument against both tube amplifiers and class A amps and especially class A tube amps  :)

I replaced Marantz MA-500 monoblocks with Nord Hypex NC500 monoblocks. The Hypex amps are awesome. The Marantz are terrific, and I was happy, but the Hypex took it to another level. Had friends come over and listen to both. Speakers are Philharmonic Audio Phil-3 with two SVS SB2000 subs, one for each channel, and preamp is Cambridge Audio A308cr and player is Rega Apollo. Outboard NAD M51 DAC.

In my own experience can’t beat these new generation Class D amps. Dead silent and ample transient power.
Now I am building myself ICEpower 1200As1 based monoblocks. Had a custom case made by Ghent Audio, who did a great job. More power can’t hurt. Considered the Benchmark AHB2, which had terrific reviews and specs. Almost bought them, but I suspected more power is better. The Benchmark noise floor is measured a bit lower, but we are in extremely low noise territory to begin with with these amps. Some links for anyone interested:
Benchmark AHB2: https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-benchmark-ahb2...
Nord Hypex NC500: https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-nord-one-nc500...
Hypex NC2K: https://www.audiosciencereview.com/forum/index.php?threads/apollon-hypex-nc2k-monoblock-amplifier-re...

ICEpower 1200AS2: https://www.audiosciencereview.com/forum/index.php?threads/apollon-as1200-review-and-teardown.9373/
Purifi 1ET400A: https://www.audiosciencereview.com/forum/index.php?threads/review-and-measurements-of-purifi-1et400a...

Benchmark has been measured to have the lowest distortion/noise. However, we are looking at levels generally below .005%
I, for one, am not going back. These amps are terribly efficient. I previously had Bryston amps that were simply great, but that was 20 years ago.

PS - I have a separate HT system where I use a $400 Crown amp to drive subwoofers (18 inch Dayton), I built.
Clearly, others have different experiences and views. I have a cousin with the exact same speakers (we purchased them together), but he swears by his Audio Research tube system and I tell him he is wasting his money, and if he wants a tube characteristic, the Schiit Freya+ is difficult to beat, though his AR reference preamplifier is simply terrific.
Have fun!

Ncore, Purify or Benchmark is where it's at. Hook one of these up to a high-quality preamp and you've just arrived at top-notch sound on a relatively bargain budget.

I have a March Audio Ncore design with a Wyred-4-Sound preamp and couldn't be happier. The next step would only be a Stage 2 on the preamp or the Benchmark HPA4.
Set your sights on better speakers after this.

I find that class D amplifier module designers or companies of that nature are looking to ’commoditize’ audio amplifiers and place themselves at the top of that ’food chain’ that they are building.

As the quality of class d rises, then more and more ears are going to find that they sound not best, but ’good enough’

when that happens, and it is happening..and you can see it in all the class d threads...when that happens, then the ’war’ for quality will be over, and then we will have two or three brands of amplifiers, for ’the great unwashed high end audio masses’.

and those two or three companies will use ’box builders’ as fame and fortune aggrandizers, or ’beasts of burden’ for THEIR module producing fame, where the box builders are invariably pushed to being simple minded idiots, capable of nothing... who are just resellers of Coke or Pepsi. Like computer builders, who use branded cards power supplies and cases..and whatnot ..for making computers.

Skilled? sort of. Barely.
But, it will happen, as there is money on the table and some will step in and be that box builder and be that maker of fortunes ---for the given class d module maker.

I know this is true as for most of the module makers, at least so far in my contacts..none of them will sell product to anyone who tries to modify or change their modules to make that box builder the preferred choice among box builders.

These class d modules are NOT PERFECT. No matter what hype may come from what company for whatever claim maybe made about perfection. As they will come out with another module tomorrow... and that new one will suddenly be ’the perfect one’.

Basically, they are iterating like they did before... and before... and before... and before...

Yet each claim is a stinky claim of audio perfection, yet each one gets replaced..

They want to sell highly branded COKE or PEPSI to YOU and to have you ignore the lowly beast of burden... and concentrate on them, the module builder.

So, I can improve their modules. Its easy. every single module I’ve seen from anyone has design flaws, design choices... that could be better and do a better job of serving the music... and and sound better than they do. I’ve got the talent and the understandings in place through about 40 years of work, to see many of those flaws, to know exactly where they lie, and what to do about them.

I’ve done it before and folks have recognized that when the given class D modules I worked on where at shows, and people hard them and said it was the best class d they’ve ever heard.

But, if I were to change that module... then you might notice... and then the next OEM box pusher might suffer in sales. As I’ve got the better module, as I’ve improved it.

I have to tell them what I plan to do with the module. I have to.I have to say it clearly, and upfront . As I can’t afford to do al the intellectual work, and make the changes, begin selling the amps, and then have access pulled.

In that scenario, I’d have all the work done..out there..and then that work stolen and used by others. and I receive nothing for all my years of study, effort, and work. Zero.

So, this ’difference’ is bad for the module company, and for bad for their ’other’ clientele. I can see their point. If I were them, I’d probably see it the same way.

And I am forbidden to buy from them for OEM use. For the sin of making the module better.

They’ve built themselves a trap. Where the customer gets the short end of the stick, especially if the customer wants the best.

It is all...basically...a steaming pile. A giant steaming pile.

I can’t give you a better class D amplifier, as I’m locked out from doing so.

How do you like them apples?