Nord MP NC252 SE Amplifier Review

[daniboun]

From Apollon amigos :

"Most of the failed modules we’ve encountered were from the first revisions of the NC252MP, specifically those manufactured between 2017 and 2020. A significant number of these failures occurred in systems that were driven hard, even with forced fan cooling, which clearly shows that airflow alone wasn’t the issue."

 

[amirm]

I never said anything about oxidisation, that was an assumption.

That was me using that word. Clearly it is not an issue in this case.

 

[wwenze]

I think there are four Nord amps reviewed on asr.

Three of those four have had issues:

1. https://www.audiosciencereview.com/...-and-measurements-of-nord-one-nc500-amp.7704/ incorrect wiring

2. https://www.audiosciencereview.com/...-se-1et400a-dual-mono-stereo-amp-review.9938/ amp shipped with incorrect fuse

3. The amp in this review.

Is this to be seen as an incredibly unfortunate series of coincidences, or a reflection on quality control?

It's just a execution of the saying: A chain is as strong as its weakest link.

The engineers are Hypex are (hopefully) paid a fine sum to create the design, the assemblers are paid......

 

[MaxwellsEq]

There are many reasons, i.e. not just oxidation, why a switch or relay contact may behave strangely over time. Even the best quality product can suffer from atomic level effects such as metal migration, e.g. if there is a DC current or even a strong electromagnetic field.

In this case it may just be simple humidity. When a device has been cold, bringing it into a warm room can cause moisture to form. At the kind of levels Amir is measuring, that may be significant.

 

[amirm]

In this case it may just be simple humidity. When a device has been cold, bringing it into a warm room can cause moisture to form. At the kind of levels Amir is measuring, that may be significant.

That's what I suggested to NORD as likely issue as the amp was in colder temp before testing.

 

[Mnyb]

That's what I suggested to NORD as likely issue as the amp was in colder temp before testing.

Tanks for the clarification , then it was an tempest in a teapot again you are quick to measure and we are quick to judge .

Suggests in indoor que , next days item brought in from the storage* the day before


*I assume that you have amassed and absurd amount of electronic products...

 

[Koeitje]

Condensation makes a lot of sense. Isn't this the second time that we had temperature affect measurements, I remember a measurement of speakers that gave a different result and it turned out being the ambient temperature affecting the speaker performance? Nothing like condensation of course, just another case of temperature in the testing environment creating artifacts.

 

[pma]

IMO there is still a channel spuriae difference that is not explained by switch contacts.
Second, I do not know about toggle switch (like the one here) that is good enough for audio. They ALWAYS have issues. Rotary switch, sealed, would be much better. I am speaking based on my experience with toggle switches in precise instrumentation.

 

[Sokel]

I built a cable converter mix'n'match box with a load of toggle switches.
I could actually affect the measurements by just touching them (no, not with bare hands, that would also include ground issues sometimes) .

Toggling them a few times and some nice contact spray made them perfect. For a while.
Rinse and repeat after some days

 

[wwenze]

Most of the time the toggle switch would only be carrying a digital signal to another switch elsewhere.

I hope.

Suddenly electronic preamp boards don't seems like a bad idea yea

 

[PJR918BMW]

Someone shared an interesting comparison: NCX252mp vs NC252mp vs Topping Pa5 II vs Purifi

See attached file

...and at say 10W real World levels. All well well below audible threshold? ...we're dancing on the head of a pin here?

Did Amir get his holiday?

 

[TNT]

I looked in my inbox here and in email but did not find a record of them contacting me. I thought they had but I can't find it. If I had, I would have run the results by them.

"It is on kind loan from a member "

No?

//

 

[amirm]

"It is on kind loan from a member "

No?

//

???

 

[dan_uk]

???

Isn't he suggesting, if its on kind loan from a member, why would the manufacturer of emailed you....

Or was the manufacturer aware a member had sent it in?

 

[Tone]

Isn't he suggesting, if its on kind loan from a member, why would the manufacturer of emailed you....

Or was the manufacturer aware a member had sent it in?

The manufacturer was not aware until minutes before my first post.

We are progressing towards a resolution given the circumstances.

And I can only thank Amir for his help so far.

 

[Tone]

And if anybody out there with Nord amplifiers that have the xlr-rca toggle switches can run some simple tests that would be helpful.

I currently have a batch of switches in the freezer.

 

[Tone]

There are many reasons, i.e. not just oxidation, why a switch or relay contact may behave strangely over time. Even the best quality product can suffer from atomic level effects such as metal migration, e.g. if there is a DC current or even a strong electromagnetic field.

In this case it may just be simple humidity. When a device has been cold, bringing it into a warm room can cause moisture to form. At the kind of levels Amir is measuring, that may be significant.

Hermetically sealed only addresses one instance of degradation, there are many factors with any mechanical connection.

Analog ic anyone?

They are much better specified more recently.

 

[Tone]

4 or 5 ohm on resistance consistent over frequency, very low distortion, and not the newest.

Just saying..

 

[amirm]

Isn't he suggesting, if its on kind loan from a member, why would the manufacturer of emailed you....

Oh. I meant that if the manufacturer had sent me equipment in the past I would have had their email. This has happened good number of times when both members and companies send me gear. In these cases, even if the manufacturer had not sent the specific item and I found issues, I would reach out to them as a courtesy.

 

[amirm]

IMO there is still a channel spuriae difference that is not explained by switch contacts.

That's correct. The noise in the one channel is constant anyway so not explained by the intermittent matter.

FYI I was remiss in the re-test in not testing the amp as is again. I toggled the switches and then tested. It is possible that the humidity or whatever the cause of the first failure was, is unrelated to the switch.