BUCKEYEAMPS Hypex NCx500 Amplifier 2channel Review

[thin bLue]

To clarify, did the review unit not have protection or it did, but if failed to work properly?

As I am not a reverse engineer, the only thing I can say is that permanent damage occurred under the test conditions mentioned above.

I personally think it's highly likely that wasn't triggered properly and was bypassed somehow.

 

[pma]

Thank you for very detailed measurements, @thin bLue . You know, nowadays the specified amplifier power is usually only a short-term power, or sometimes it even can never be achieved.

 

[Toni Mas]

No, it definitely should have self protected this 4 ohms torture test without a problem.

Why push the gear to its limits?
Dont understand...

 

[howard416]

Why push the gear to its limits?
Dont understand...

Because you should be able to. If you buy an apple, you expect to do with it anything that an apple can. Or, if it were up to you, you would only eat the skin?

 

[Toni Mas]

Because you should be able to. If you buy an apple, you expect to do with it anything that an apple can. Or, if it were up to you, you would only eat the skin?

No! No need to break anything!

 

[thin bLue]

I became annoyed at all the similar graphs and skimmed and scanned the stuff. Too many images and not enough details in text. (My bad!)

Really sad words to me.

Graph seems similar means 1. Measurements are reproducible. 2. DUT also make reproducible result as well. <- nice 3. Data can be compared
The ultimate goal is to obtain exactly the same values from exactly the same measurements. <- impossible.

I still vividly remember what a catastrophe it was when I made detailed comments.

1. There are many things I don't know well, so the quality of the explanation is low.
2. I come into conflict with people with different views.
3. The more I increase the explanation, the more likely I express things more non-objective. Because I am 'person' (=imperfaction)

However, data is simply data, if the measurement conditions are specified, and anyone can interpret it in any way they wish.

 

[howard416]

No! No need to break anything!

You’ve never floored it in a car before? Or slammed on the brakes? Or used the highest temperature setting on your oven?

 

[thin bLue]

I think that without the failure we would see this graphs x2 (and that means in all 3 gain modes we saw in 4 Ohms! )

Yes xD
2 Ohms measurement was scheduled in the same way!

 

[Apollon Audio]

Slovenia has 230V.
Calcs still fall a little short.

Edit:does Apollon uses extra heatshink?Maybe that helps.

We actually have 245V here. The SMPS1200 outputs 90DC on both rails at this voltage. With 230V or 110V you should get at least 600 watts per channel @4Ohm with one SMPS1200 power supply.

That is why I open whole setting.

With really short term test with much less measurement point could disguise instantaneous squeeze out of capacitors as regular output.
(less point = way faster process)

View attachment 303768
little different case but it will help to understand.
You can see way deeper it goes down before inflection point with 31 points than 200.
less pointed one spend way less time at high power zone = less heat = less harsh load.

There must be something wrong with the power supply in this test. I've measured the same setup with my APX555b, so two NCx500 modules with one SMPS1200A700 power supply and got this at lowest gain setting. Buffer not bypassed.

 

[MaxwellsEq]

No! No need to break anything!

He didn't set out to break it. The specifications state that it can do "x". When he asked it do "x" it broke.

 

[MaxwellsEq]

We actually have 245V here. The SMPS1200 outputs 90DC on both rails at this voltage.

There must be something wrong with the power supply in this test. I've measured the same setup with my APX555b, so two NCx500 modules with one SMPS1200A700 power supply and got this at lowest gain setting. Buffer not bypassed.

Which is a good point. This PSU may have been faulty from the start.

 

[GXAlan]

Now days, Consumer amplifiers also need to be protected just as well as concert halls.
With the advent of the latest Class D amplifiers, power levels are climbing enormous with time, which means that more protection is required.
100% agree with you.

We need protection on speakers as well!

To put some things into perspective, Marantz has its PM-10 running bridged HypeX NC500OEM, not the NCx500OEM, but they choose to only use a SMPS600 for each pair. They also rate it for 200W into 8 ohms only and 400W into 4 ohms even though the BRIDGED NC500 could do more.

There was a lot of discussion about the extra effort Marantz put into reliability in various interviews since it was their first high end Class D amp.

The service manual highlights the protection circuits that Marantz puts in (white), the protection circuits by the NC500 and the protection setup by the SMPS600. I don’t know if these are in the Model 30.

 

[sarumbear]

No! No need to break anything!

The tester was not aiming to break anything. They read the specs and tested to confirm if they are true or not. Don’t you want to be sure if the manufacturer is true to their words?

 

[thin bLue]

I agree.

@thin bLue may I suggest you to add a summary section? Like the abstract on a research paper.

Thank you for listening.

If somebody pays me lots of Pizza, then I'll seriously consider your suggestion!

 

[thin bLue]

Thank you for very detailed measurements, @thin bLue . You know, nowadays the specified amplifier power is usually only a short-term power, or sometimes it even can never be achieved.

Through the process of consumer amplifiers being tested and some of them fried, we look forward to a future where only well-protected amplifiers remain on the market that all consumers can trust and buy. thank you!

 

[thin bLue]

Why push the gear to its limits?
Dont understand...

It was just rated power! I didn't think running on limit-tensioned edge.
And limits <- It should be the point after protection triggered so It should be an area that is forever out of reach for the average consumer(including me).

 

[thin bLue]

Because you should be able to. If you buy an apple, you expect to do with it anything that an apple can. Or, if it were up to you, you would only eat the skin?

That's the point!

 

[GXAlan]

Through the process of consumer amplifiers being tested and some of them fried, we look forward to a future where only well-protected amplifiers remain on the market that all consumers can trust and buy. thank you!

+1 for this.

Reliability is important for a number of reasons, ranging from protecting downstream speakers, to social responsibility not to increase our electronics landfill. I don’t think anyone is asking every product to have a 50 year operational life span, but it should meet advertised specifications and in the modern day, things like DC protection or overcurrent protection unless you are dealing with stuff like vintage tubes (for overcurrent issues).

Still, this reliability is often why DIY products are a lot cheaper than commercial options. I am curious what sort of protections you get with the AMP10 from Marantz…

 

[thin bLue]

We actually have 245V here. The SMPS1200 outputs 90DC on both rails at this voltage. With 230V or 110V you should get at least 600 watts per channel @4Ohm with one SMPS1200 power supply.

There must be something wrong with the power supply in this test. I've measured the same setup with my APX555b, so two NCx500 modules with one SMPS1200A700 power supply and got this at lowest gain setting. Buffer not bypassed.

Thank you for your response.

Since the test I did was conducted with 150 points, I spend a much longer time in the high power area. Therefore, it is expected that the protection circuit will operate quickly in the area where continuous output is impossible.

If your design was designed and tested to handle short peaks safely, expect to see a slightly different graph since this test is testing a more leisurely(?), gradual power increase than short peaks.

By the way, the illuminated front panel is a really cool look!

 

[thin bLue]

Which is a good point. This PSU may have been faulty from the start.

If so, we can test again after replace the PSU!