New AUDIOPHONICS MPA-M500NC 374 euro = 415usd for monoblock NC500!

[Koeitje]

We can send him an amp if he wants, but he's generally very busy.
And these amps are not very customized, maybe it will be more interesting for NC500OEM / ET400 models.

Will you make NC500OEM and ET400 models?

If you have objective reproachs to do about the chassis here or in PM feel free to give your opinion.
It can help to improve things.

I just like very clean designs, but the stereo case has that smooth rectangle around the power button. I also don't like the very rounded corners, but I can live with that. The power buttons on your mono cases are much nicer in my humble opinion, and I like the horizontal line on them. The best looking cases I've seen are from Ghent audio.

 

[rodtor]

We can send him an amp if he wants, but he's generally very busy.
And these amps are not very customized, maybe it will be more interesting for NC500OEM / ET400 models.

The NC400 has been tested here, but not with the power supply recommended by Hypex. I think that many of us would be interested in seeing your assembly of this product measured by Amir.

 

[Audiophonics]

Will you make NC500OEM and ET400 models?

The power buttons on your mono cases are much nicer in my humble opinion, and I like the horizontal line on them.

Understood about the chassis, I also think the power button design can be improved, I will think about it for the next batch.
Yes we made a driver board, both should come soon. Assembled into the big HPA chassis and into a new one, a little wider than MPA ones.

The NC400 has been tested here, but not with the power supply recommended by Hypex.

It's up to Amir to decide, we can send him any that he wants.

 

[Zoomer]

we made a driver board

@Audiophonics Will this be sold separately for the DIY-ers ?

 

[On7green]

It's up to Amir to decide, we can send him any that he wants.

New here, but I am also looking at purchasing a NC based (proably mono) Audiophonics model. Testing of a 250, 400, or 500 unit would be of interest to me.

 

[Xyrium]

You've sent a couple of your DACs to Amir for testing in the past. Any chance you could send an amp such as the MPA-S250NC? This looks like all the amp that most of us would ever need at a price that looks too good to be true!

I'm pretty sure that equates to 50W/channel "continuous (yes, the debate rages on), if we were to equally spec it against common integrateds or amps from the usual class A/B mass market suspects (Yamaha, Marantz, etc.).

https://www.hypex.nl/documenten/download/909

Edit: BTW, I rather like the cases, reminds me of the ATI stuff, industrial.

We can send him an amp if he wants, but he's generally very busy.
And these amps are not very customized, maybe it will be more interesting for NC500OEM / ET400 models.

I say one NC500 and one NC400 mono. The stereo versions shouldn't differ. That way, we have one SMPS per amp module for the NC400, and the integrated version in the NC500. Then again, I believe he's tested one with an NC400 and dedicated SMPS.

Just make that an NC500MP and NC502MP. He's done both NC400 and 500's before.

 

[VintageFlanker]

I'm pretty sure that equates to 50W/channel "continuous (yes, the debate rages on), if we were to equally spec it against common integrateds or amps from the usual class A/B mass market suspects (Yamaha, Marantz, etc.).

No.

The NC250MP alone hasn't been measured yet, but: You can already see in IOM NC252MP review how far it can go regarding power:

The meat of any amplifier review is power versus distortion and noise. Here it is at 4 ohm:

Shame to see the early rise in distortion starting at 20 watts. That aside, you have considerable amount of power clocking at 236 watts, both channels driven in this tiny enclosure.

Switching to 8 ohm load we get:

Now the early rise in distortion is more modest. We get 125 watts of power at a SINAD of 91 db. Interesting to compare it to Purifi 1E400A which produces similar power but a whopping 130 dB SINAD or 40 dB better!

Peak power is sadly not much more than steady state due likely to regulated power supplies:

And no, regular Class AB amps don't perform that much better... not to mention worse in most case.

 

[Xyrium]

While they do have impressive max/dynamic power, their continuous is not the same, as per the spec sheet I linked. The 252 is a 50W continuous board. So, let's say we run the full frequency spectrum on that amp for 5+ minutes....what are we going to see?

They're still one of the most impressive dynamic headroom options out there. Even if you idle at 50W in loud listening, they somehow still have hundreds of Watts on tap for the bursts/crescendos. So, if I were to say that this is "all the amp that one would ever need", I'd be referring to the NC400 or greater. IMHO, of course.

 

[VintageFlanker]

So, let's say we run the full frequency spectrum on that amp for 5+ minutes....what are we going to see?

Ask @March Audio to find out!

 

[March Audio]

While they do have impressive max/dynamic power, their continuous is not the same, as per the spec sheet I linked. The 252 is a 50W continuous board. So, let's say we run the full frequency spectrum on that amp for 5+ minutes....what are we going to see?

They're still one of the most impressive dynamic headroom options out there. Even if you idle at 50W in loud listening, they somehow still have hundreds of Watts on tap for the bursts/crescendos. So, if I were to say that this is "all the amp that one would ever need", I'd be referring to the NC400 or greater. IMHO, of course.

If the design has adequate heat sinking it does exactly what it says on the tin. It maintains 250 watts into 4 Ohms.

This has been explained several times. I posted a video of it doing this.

 

[Xyrium]

If the design has adequate heat sinking it does exactly what it says on the tin. It maintains 250 watts into 4 Ohms.

This has been explained several times. I posted a video of it doing this.

Perhaps, but it has also been explained that even a single NC400 with a dedicated SMPS600 will literally shut down, and practically cook the internals long before 5 minutes of run time has been reached. https://www.audiosciencereview.com/...ments-of-hypex-nc400-diy-amp.5907/post-134676

If you've performed this same test without a problem, kudos to your implementation of these boards! This is not an attack on you, but a continued discussion about what some of these implementation can, or cannot do. One can heatsink the daylight (literally) out of some of the components to get them to run stable outside of their design spec, but other components will probably fail prematurely, and perhaps, catastrophically.

As I may have mentioned, I have an NAD using the old UcD Hypex boards, and for its intended purpose, it works well. Believe me, I love the idea: gigwatt power and SOTA specs at only 5 lbs of weight. It's a dream come true for sure, especially for DIYers, since these are literally plug and play once you obtain the connectors. Man, that dynamic headroom is to die for!

Anyway, thank you for taking the time to entertain my ramblings! I appreciate the experience and knowledge you bring to this forum, and hope such discussions will continue to bring out new testing standards and greater understanding of this technology.

 

[March Audio]

Which is not an Nc252 unit.
. The 252 has a large bottom plate which the semiconductors are attached. This will attach to the enclosure.

Hypex are quite explicit about the implementation, usage and limitations of those power supplies in that link. They are intended for music reproduction not continuous signals that only ever occur on a test bench.

That psu is inadequate for 2 channels of nc400

 

[AudioSceptic]

If the design has adequate heat sinking it does exactly what it says on the tin. It maintains 250 watts into 4 Ohms.

This has been explained several times. I posted a video of it doing this.

That's what I thought, assuming an adequate power supply, of course.

 

[Xyrium]

Which is not an Nc252 unit.
. The 252 has a large bottom plate which the semiconductors are attached. This will attach to the enclosure.

Hypex are quite explicit about the implementation, usage and limitations of those power supplies in that link. They are intended for music reproduction not continuous signals that only occur on a test bench.

That psu is inadequate for 2 channels of nc400

Good stuff about the 252. Does the 502 have that as well? I'm rather interested in that board.

Just to clarify, the test linked was one to one, PSU to power module, not two NC400's.

 

[March Audio]

Good stuff about the 252. Does the 502 have that as well? I'm rather interested in that board.

Just to clarify, the test linked was one to one, PSU to power module, not two NC400's.

Yes the 502 is similar to the 252 in this respect.

I appreciate the linked test was one channel driven. First point is the design of that particular psu is not intended for continuous power and Hypex are explicit about this.

Second point is that real music actually has a low rms (average) power level. It's typically only around 1/5th of the peak. So in real world usage any amp of any Class will be operating well below its continuous rating. A P502 just starting to clip on peaks might only be around 100 watts rms (average). It varies with music content but even some heavily compressed rock /pop is very unlikely to reach 200 watts rms (average).

As such long term continuous power is a pretty useless metric.

 

[vrøvl]

Has anyone compared the equivalent models from Audiophonics and March Audio?

I guess measurements would be more or less identical?

I'm specifically interested in the NC252MP models, but the question is valid for the whole range.

The March looks to have a better/more beautiful chassis based on images. While the Audiophonics looks more DIY at first glance?
(I also looked at the IOM but the inside looks a little too DIY for my liking,)

Is the build quality and cosmetics of the March vs Audiophonics worth the price difference?
Any other differences to consider?

Audiophonics MPA-S250NC - EUR 390 ex tax
March Audio P252 - USD 895 = EUR 803 ex tax

 

[PuX]

Audiophonics HPA-S400NC
this one screams "please test me"

by the way, what kind of preamp would be recommended to use with it?

 

[Xyrium]

I suspect you'd see results very similar to the nc400 homebrew that was tested, when testing only the single channel.

https://www.audiosciencereview.com/...ments-of-hypex-nc400-diy-amp.5907/post-134676

It;s a lengthy thread however, and worth the read if you're considering making a purchase.

 

[Nathan_A]

I'm considering picking up a pair of NC400 monos or a pair of NC500MP monos to drive my ONIX Reference 3's as an alternative to my Yamaha MX-1 to see how Class D has been shaping up. The only Class D amplification that I've used on these speakers is the Pioneer D3 amps in my SC-65 (which really sounded pretty great for an AV receiver.

One of the things I wonder is what the estimated SINAD would be of the MX-1 based on its specs, and the other thing I wonder is the real difference between the NC400 and NC500MP in terms of audible differences under what circumstances?

 

[Xyrium]

I'm considering picking up a pair of NC400 monos or a pair of NC500MP monos to drive my ONIX Reference 3's as an alternative to my Yamaha MX-1 to see how Class D has been shaping up. The only Class D amplification that I've used on these speakers is the Pioneer D3 amps in my SC-65 (which really sounded pretty great for an AV receiver.

One of the things I wonder is what the estimated SINAD would be of the MX-1 based on its specs, and the other thing I wonder is the real difference between the NC400 and NC500MP in terms of audible differences under what circumstances?

If your MX-1 is in good shape, I'm thinking your sound is in good shape. I doubt a new amp will improve upon that model. Isn't it full dual mono as well?

Is there something missing from your music? The Onix stuff was a great mid-high end parts bin run, IMO. I'm not so sure their x-overs were calculated perfectly. The use of that ring tweeter required a fairly high xover point, something like 4k. If they didn't do that properly, I can see you potentially hearing some issues. However, it sounds like you have a nice setup already, which would probably require a better room/placement, for the sound to improve, IMHO.

BTW, I'd love to see Amir test the MX-1 if you have the ability to send her in!