Buckeye NC252MP Stereo Amplifier Review

[Geert]

Likely power supply.

From the images on Buckeye's website this seems to be a single OEM board implementation, there's no separate power supply board. It should be exactly the same board as in the Audiophonics-mpa-s250nc-amp-review which doesn't show the 20Hz linearity issue (although it also has reduced power at 20Hz). However, comparing the pictures there's one small difference I notice, the orientation of the coil next to the 2 large caps. Did Hypex make different versions of this board, one having worse performance?

 

[Sokel]

From the images on Buckeye's website this seems to be a single OEM board implementation, there's no separate power supply board. It should be exactly the same board as in the Audiophonics-mpa-s250nc-amp-review which doesn't show the 20Hz linearity issue. However, comparing the pictures there's one small difference I notice, the orientation of the coil next to the 2 large caps. Did Hypex make different versions of this board, one having worse performance?

They also state 180 watt per channel @2 Ohm which is not the case here as the amp got into protection trying to get that low.

Edit: I know nothing about this modules and whether they have have universal mains but if not is there a chance it's wrongly configured for 240V?

 

[MrHifiTunes]

Is this the same amplifier as the hypex fa252 plate amp?

 

[pickyAudiophile]

Nice to see these certification tags from all around the globe on rear . ...MP series thankfully will accept anything from 110V to 240V, so they might have said to themselves: why labelling then? However, what about that burn-through fuse then, shouldn't that one be labelled with swapping instructions at least?

 

[Geert]

From the images on Buckeye's website this seems to be a single OEM board implementation, there's no separate power supply board. It should be exactly the same board as in the Audiophonics-mpa-s250nc-amp-review which doesn't show the 20Hz linearity issue (although it also has reduced power at 20Hz). However, comparing the pictures there's one small difference I notice, the orientation of the coil next to the 2 large caps. Did Hypex make different versions of this board, one having worse performance?

To answer my own question; I found datasheets of 2 versions of the board, showing the differences in the power supply section:

• https://vtvamplifier.com/wp-content/uploads/2020/04/NC252MP_02xx.pdf
• https://www.hypex.nl/media/47/17/ef/1646058029/NC252MP_04xx.pdf

One difference in the specs; the older board has a lower output impedance. The measurements in the datasheets also show far better linearity for the older board (no hump in the higher frequencies):

 

[Sokel]

Is this the same amplifier as the hypex fa252 plate amp?

It sure looks similar:

 

[AudioSceptic]

Nice performance, pedestrian design.

You're certainly not going to buy this for its style or finish, and the price means all the money is spent on where it really matters.

 

[delta76]

Realized that Amir never measured a NC502MP-based stereo amp (he did review a 6 channels I think), it should be at the sweet point between power, SINAD and price

 

[daniboun]

From the images on Buckeye's website this seems to be a single OEM board implementation, there's no separate power supply board. It should be exactly the same board as in the Audiophonics-mpa-s250nc-amp-review which doesn't show the 20Hz linearity issue. However, comparing the pictures there's one small difference I notice, the orientation of the coil next to the 2 large caps. Did Hypex make different versions of this board, one having worse performance?

Amigos,

The NC252MP is the same on all NC252 amps...only the design and the options differ from one manufacturer to another...
Buckeye just took a low-cost enclosuse BUT What may differ, however, are the module revisions.

 

[daniboun]

Realized that Amir never measured a NC502MP-based stereo amp (he did review a 6 channels I think), it should be at the sweet point between power, SINAD and price

Checkout for the dual channels :

Hypex NC502MP Power Sweeps and Distortion Measurements

Hypex NC502MP Power Sweeps and Distortion Measurements

analog-precision.com

 

[daniboun]

Let's compare with the IOM NCore Pro, Hypex NC252MP from September 2019. = old revision (July 2019 / NC252MP_02)

Review and Measurements of IOM NCore Pro PWR Amp

This is a review and detailed measurements of the IOM NCore Pro, Hypex NC252MP class-d based stereo power amplifier. It was kindly purchased by a member and drop shipped to me. It costs €669 from the company website. The IOM Ncore Pro comes in very compact and solid enclosure: The on/off...

www.audiosciencereview.com

 

[Geert]

What may differ, however, are the module revisions.

That's what I meant with ´versions´.

 

[Sokel]

Amigos,

The NC252MP is the same on all NC252 amps...only the design and the options differ from one manufacturer to another...
Buckeye just took a low-cost enclosuse BUT What may differ, however, are the module revisions.

View attachment 315102

Manufacturers have the option to make customs versions as it seems.
Here's the @pma 's built for example:

PMA-NC252MP power amplifier

PMA-NC252MP As a manufacturer of electronic equipment I have been granted a web account for Hypex OEM web shop. My newly designed power amplifier based on excellent Hypex NCore modules is PMA-NC252MP. It is an amplifier with rated power 2x250W/4ohm and based on the NC252MP OEM modules. Hypex...

www.audiosciencereview.com

 

[delta76]

Checkout for the dual channels :

Hypex NC502MP Power Sweeps and Distortion Measurements

Hypex NC502MP Power Sweeps and Distortion Measurements

analog-precision.com

good link, but Amir's tests are more comprehensive, and it makes it easier to compare between similar amps.

 

[daniboun]

That's what I meant with ´versions´.

Yepppp indeed ) look above at the measurements of the OM NCore Pro, Hypex NC252MP with older revision.

 

[Willem]

Yes the case is cheap looking. However, since the amp has both auto on/off and a trigger, you can safely and conveniently keep it out of sight in a cupboard or whatever. Esthetically, that would be my ideal power amplifier.

 

[Matias]

To answer my own question; I found datasheets of 2 versions of the board, showing the differences in the power supply section:

• https://vtvamplifier.com/wp-content/uploads/2020/04/NC252MP_02xx.pdf
• https://www.hypex.nl/media/47/17/ef/1646058029/NC252MP_04xx.pdf

One difference in the specs; the older board has a lower output impedance. The measurements in the datasheets also show far better linearity for the older board (no hump in the higher frequencies):

View attachment 315095

They tweaked the module for lower noise floor (the descending slope part), and the new hump is revealed (also tiny little higher). IMO a good trade off choice was made.

 

[Sokel]

They tweaked the module for lower noise floor (the descending slope part), and the new hump is revealed (also tiny little higher). IMO a good trade off choice was made.

Neither of these are the problem here.
The main problem is it doesn't meet its specs at 2 Ohm as it failed to pass Amir's tests.
Combined with the "anomaly" at 20Hz seems that there something out of order there.

 

[KxDx]

??

AI ain't what it used to be.

 

[Dennis_FL]

I own this amp (in a different case) and am very pleased. I have it set on "Auto" and it turns on/off by signal sensing and I never heard an audible speaker noise with either. My wish list for the future model is a power button in the front (when I want to use my headphone amp and want to turn off the main speakers).