AUDIOPHONICS MPA-S250NC Amp Review

[Acerun]

I also use a Wiim for bit perfect streaming either through the Denon or through my RME to this amp. Really good value to be had here.

 

[dweeeeb2]

I have exactly this - Wiim & Flex in a small room - but with the Buckeye amp in a Ghent case. Also a Topping EX5 for headphone use. Only 1 sub though. I love my setup.

yep, Im between the 2 amps as well. Thinking buckeye due to their appearance on here. Not purchasing just yet as it will be a second system so funding considerations at the moment….

 

[Rottmannash]

It does. 1% is -40dB and it's right on the nose.

Also, minor variations in mains voltage will cause variations in measured output. The power supply in reality switches in a voltage doubler for US supplies.

I have a question. Here in the US voltages are 110. If one uses a 220V plug will the amp produce more power?

 

[Snix]

Topping engineers: "WHAT? Where is the twice-the-size-of-the-amp power brick?! What kind of dark magic is this?!"

jk aside, now I kinda want to know if moving the switching power supply away from the middle of unit would improve SINAD a bit...

 

[amirm]

As the Hypex NC250MP is rated for 2 ohm operation, does this mean this amp failed at 2 ohms?

I only tried it once and it produced very little voltage so I didn't push it more.

 

[pma]

I only tried it once and it produced very little voltage so I didn't push it more.

With a resistor (2ohm, 0deg), or with a +/-60deg inductive/capacitive component added? I guess the pure 2ohm resistive should work?

 

[amirm]

I was trying resistive. AP test is tricky here as I have to set the voltage for 8 ohm which heavily overdrives the amp into 2 ohm. If the recovery is not fast enough from protection, you get the results I had. I can't get AP interested in fixing this issue so longer term have to write my own automation.

 

[Rick Sykora]

I only tried it once and it produced very little voltage so I didn't push it more.

Yes, I had to run REW’s power vs distortion test a few times to get results. Once protection kicked in, would not get results either and was with simple resistive load too. As @pma shows, the amp does produce substantive output at 2 ohms. My new test rig is very comparable to his. Always good to know whether the test may be limiting the outcome though.

 

[pma]

Always good to know whether the test may be limiting the outcome though.

Exactly. Could not say it better. Just to mention, “tailored” tests are quite time consuming.

 

[AudioSceptic]

This is a review and detailed measurements of the AUDIOPHONICS MPA-S250NC stereo Ncore class D amplifier. It is on kind loan from a member and costs 415,83 € tax excl. (US $444).
View attachment 290337
The enclosure is absolutely adorable! While it is fair bit deep, the other two dimensions are quite small. Combined with the low weight of the unit, you feel like buying a dozen to spread around the house and two to take on the road with you! The power button feels quite nice. The rear terminals exude quality and would rival and beat what you find on many expensive amplifiers:
View attachment 290338
Nice to see trigger input as well.

Inside a Hypex NC252MP amplifier module with integrated switching power supply. In use the bottom front got somewhat warm but nothing of concern. Protection circuit is robust and auto recovers from overloads.

If you are not familiar with my amplifier measurements, I highly suggest watching this video on amplifier measurements.

AUDIOPHONICS MPA-S250NC Measurements
Let's start with our dashboard:
View attachment 290340

That is very competent performance as far as noise+distortion (SINAD):
View attachment 290341

Zooming in:
View attachment 290342

Noise performance is excellent:
View attachment 290343

Class D designs can suffer from load dependencies but we can count on Hypex modules to be free of this:

View attachment 290344

Crosstalk is very good despite both channels being on the same module:
View attachment 290345
Multitone test showcases the low distortion:
View attachment 290346

Dual tone 19+20 kHz shows the same:
View attachment 290347
Only a couple of sidebands are visible at -98 dB and lower in audible band.

Power curve was very clean with 4 ohm load:
View attachment 290349

But strangely rose a bit with 8 ohm load:
View attachment 290348

Back to 4 ohm, we almost get the specified level of power:
View attachment 290350

I was pleased with rather smooth power vs distortion vs frequency:
View attachment 290351

The MPA-S250NC passed my stress test with reactive loads of 4 and 8 ohm but shut down into 2 ohm:
View attachment 290352

There is fair bit of pop on and off noise:
View attachment 290353

Finally, the amplifier is stable and ready to go on power on:
View attachment 290354

Conclusions
Audiophonics has produced one adorable stereo amplifier! I just want to sit there and look at it. Fortunately beauty goes beyond the skin, sporting a performance Hypex class D amplifier, producing top class results in all the measurements. You get near state of the art performance at bargain prices with scant space needed to dedicate to the amplifier.

I am happy to recommend the AUDIOPHONICS MPA-S250NC. Can't stop smiling.....

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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Very nice. I'd go for the 2 x mono version, so each can go close to the speaker with short speaker cables. They would be easy to hide it you wanted. <https://www.audiophonics.fr/en/powe...-mono-ncore-nc250mp-1x250w-4-ohm-p-14445.html>

 

[AudioSceptic]

I replaced that same Parasound with one of these. I actually laughed out loud when I took the Audiophonics out of the box. The Parasound weighs about ten times more, and is four times the size. You can put one of these things anywhere.

Yes, it's hard to tell from the photos but it's only 141x357x65mm.

 

[Thomas_A]

I have three of them that trigger on when I turn on my Denon X8500H and I hear no pop.

Thanks for this. Another question, how did you connect the three to the Denon trigger? If I have one trigger out and two amps, what's the best way to split?

 

[TNT]

I have a question. Here in the US voltages are 110. If one uses a 220V plug will the amp produce more power?

No because the power unit in the amp sees to that the amp stage is fed the same voltage whatever the mains.

//

 

[Acerun]

Thanks for this. Another question, how did you connect the three to the Denon trigger? If I have one trigger out and two amps, what's the best way to split?

https://a.co/d/97gNDeo and two trigger cables. And actually for my three amps, I bought two of those splitters.

 

[pma]

No because the power unit in the amp sees to that the amp stage is fed the same voltage whatever the mains.

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No, it does not have regulation. You may have 100-120V or 200-240V, switchable. And output power depends.

 

[TNT]

NC252MP is auto switching and there is no sign in specifications of output power being qualified vs. mains voltage. So, no

https://www.hypex.nl/media/70/e9/cc/1646058029/NC252MP_01xx.pdf

//

 

[pma]

I have added more measurements of NC252MP into 2ohm resistive load, here:

 

[pma]

NC252MP is auto switching and there is no sign in specifications of output power being qualified vs. mains voltage. So, no

https://www.hypex.nl/media/70/e9/cc/1646058029/NC252MP_01xx.pdf

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The datasheet is not helpful. Hypex power supplies are SMPS, but not like PC power supplies that accept 90 - 240V input. Their voltage varies with input voltage.

Regulation of SMPS in power amps

There’s an interesting difference in measured power between the Purifi 1ET400A EVAL1 amp with a Hypex SMPS 1200A400 (131/257W pre-clip, 205/380 at 1%, ASR) and the same amp with the NAD SMPS in the C298 (180/415 pre-clip, 269/528 at 1%, SSN). As I understand it, this is due to differences in...

www.audiosciencereview.com

There is a jumper to select low input voltage (100-120) or high input voltage (200-240). +/-10% input difference makes the same at the output. Switching power supply does not mean it is regulated according to input level. Make your own measurements, if your opinion is still different.

 

[TNT]

"Features: Auto-switching (115/230V)"

So, no. The specification is maintained for both mains types. That was the original question. Why complicate things?

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[pma]

"Features: Auto-switching (115/230V)"

So, no. The specification is maintained for both mains types. That was the original question. Why complicate things?

//

The original question was if the output power would vary with mains voltage 110V. And it would, someone may have 105V at home and the other one 115V and they will measure different maximum output power. Same here, I have 240V and my amp thus gives higher power than if someone has 225V at home. This is the key, with Hypex SMPS the output power depends on actual mains voltage.