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Hypex Nilai500DIY Amplifier Review

Rate this amplifier:

  • 1. Poor (headless panther)

    Votes: 4 1.1%
  • 2. Not terrible (postman panther)

    Votes: 14 3.8%
  • 3. Fine (happy panther)

    Votes: 74 20.1%
  • 4. Great (golfing panther)

    Votes: 276 75.0%

  • Total voters
    368

tmtomh

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A two tone IMD test will expose any inherent HF non-linearity and does not require bandwidths of >21 kHz since the intermod components are folded down into the audio band.

Yes - but he doesn't want to test the HF linearity that way, because it doesn't produce the results he's obsessed with talking about.
 

Skeeter

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Given the HF distortion profile, I suspect the two tone IMD results won’t be good. Getting amplifier mA to show good distortion at 1 kHz is relatively easy, but it gets harder at HF. -110 dBr full 2 tone output power would be a good result.
 

restorer-john

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Limiting BW to 22kHz or so is done only for manufacturer's marketing benefit.

Sadly, there's a cohort who feel its their duty to religiously prosecute the narrative that 20-20kHz is all that matters. Because a deeply vested interest wrote a white paper or they read something a guru wrote and took it to heart as gospel.

But, if you or I had created Class D amplifiers like Hypex or Purifi, we'd attempt to paint them in the best light possible- I've said that before. But I wouldn't stoop to blatant misrepresentation and neither would you. Pure marketing wins and it seems, some people are falling for it. Not me.

I have power amplifiers where the HF distortion is precisely trimmed to a minimum level during setup. A 20kHz signal is injected and the harmonics (up to 200kHz) are monitored and the HF THD trim is tweaked to a minimum. That is so they produce their rated (0.003%) THD across the entire specified bandwidth and meet their advertised specifications in accordance with regulations. Try doing that with a 20kHz measurement bandwidth.

1677365550337.png


Another, a 1982 Perreaux PMF-2150B 200wpc@8R/400wpc@4R power amplifier has a rated THD at 20kHz and 200 watts RMS continuous of 0.009% or lower. The HF THD adjustment must be made at full power and at 20kHz, monitoring harmonics. Try that with a Class D. The last one I adjusted, was 0.004% at 20kHz at 200w. A difficult trim, but they took their responsibilities to adhere to specifications seriously.

1677365345235.png




Hypex/Purifi et al, just throw all that out the window and draw a line at 20kHz and say "nothing to see here- move along". Their THD, power and efficiency numbers have been, continue to be and likely will remain, cherry picked. That is until some authority pulls them up and requires honest disclosure.

But we have more in common than not. Everyone here on ASR is interested in fidelity, music and HiFi gear. Some people come at it a different way than others and place more emphasis on standards and disclosure- others just want to press a button and listen to music. Everyone is different.
 

Julf

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Sadly, there's a cohort who feel its their duty to religiously prosecute the narrative that 20-20kHz is all that matters.

Sadly there is also a cohort who seem to feel it is their duty to try to come up with reasons why technology that is different from what they are used to is bad. They don't even provide any evidence, they just appeal to authority, supposed expertise or just handed down audiophile folklore.
 

pma

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The HF distortion profile is more like that of a zero global feed back amp. Simple question: why is this?

A two tone IMD test will expose any inherent HF non-linearity and does not require bandwidths of >21 kHz since the intermod components are folded down into the audio band.
Such explanation (“like that of zero global feedback amp”) would be a big misunderstanding. The reason is related to feedback loop complex transfer function that corrects the switching amplifier nonlinearities. Multiple poles and is optimized <=20kHz. It shapes and pushes distortion and noise energy >20kHz, similarly as DSD for SACD. This leads to rising noise AND distortion components above 20kHz. This behaviour is inevitable and will remain unless more ideal power switching devices would be available. GaNs are not the case.
This is what it is. Just circuit behaviour. No need for emotions, but also no need for hiding and neglecting facts.
 

Skeeter

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I was commenting on the shape of the distortion curve not how the feedback works. That the Hypex amp use multi-pole feedback compensation is well documented. In the distortion graph shown it bulges between c 7 kHz and HF and espec on the higher order harmonics. One of them is at -80 dB which is high in my view for an amp showing single tone ppm level distortion at 1 kHz. This is not the distortion profile of an ultra low distortion amplifier which is how it’s marketed, so I’m simply asking why this is the case.
 

pma

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Sadly, there's a cohort who feel its their duty to religiously prosecute the narrative that 20-20kHz is all that matters. Because a deeply vested interest wrote a white paper or they read something a guru wrote and took it to heart as gospel.

Another, a 1982 Perreaux PMF-2150B 200wpc@8R/400wpc@4R power amplifier has a rated THD at 20kHz and 200 watts RMS continuous of 0.009% or lower. The HF THD adjustment must be made at full power and at 20kHz, monitoring harmonics. Try that with a Class D. The last one I adjusted, was 0.004% at 20kHz at 200w. A difficult trim, but they took their responsibilities to adhere to specifications seriously.

View attachment 267493



Hypex/Purifi et al, just throw all that out the window and draw a line at 20kHz and say "nothing to see here- move along". Their THD, power and efficiency numbers have been, continue to be and likely will remain, cherry picked. That is until some authority pulls them up and requires honest disclosure.

But we have more in common than not. Everyone here on ASR is interested in fidelity, music and HiFi gear. Some people come at it a different way than others and place more emphasis on standards and disclosure- others just want to press a button and listen to music. Everyone is different.

So measurements below are made properly, right, taking into account the fact that @BW90kHz is the maximum I can get with my instrumentation. The result is not SOTA, but definitely not bad, good old class AB.

A250W4R_BW90kHz_101W4R_20kHz.png


A250W4R_BW90kHz_thdnlevel_20kHz.png
 

Rob Fens

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Sadly, there's a cohort who feel its their duty to religiously prosecute the narrative that 20-20kHz is all that matters. Because a deeply vested interest wrote a white paper or they read something a guru wrote and took it to heart as gospel.

But, if you or I had created Class D amplifiers like Hypex or Purifi, we'd attempt to paint them in the best light possible- I've said that before. But I wouldn't stoop to blatant misrepresentation and neither would you. Pure marketing wins and it seems, some people are falling for it. Not me.

I have power amplifiers where the HF distortion is precisely trimmed to a minimum level during setup. A 20kHz signal is injected and the harmonics (up to 200kHz) are monitored and the HF THD trim is tweaked to a minimum. That is so they produce their rated (0.003%) THD across the entire specified bandwidth and meet their advertised specifications in accordance with regulations. Try doing that with a 20kHz measurement bandwidth.

View attachment 267495

Another, a 1982 Perreaux PMF-2150B 200wpc@8R/400wpc@4R power amplifier has a rated THD at 20kHz and 200 watts RMS continuous of 0.009% or lower. The HF THD adjustment must be made at full power and at 20kHz, monitoring harmonics. Try that with a Class D. The last one I adjusted, was 0.004% at 20kHz at 200w. A difficult trim, but they took their responsibilities to adhere to specifications seriously.

View attachment 267493



Hypex/Purifi et al, just throw all that out the window and draw a line at 20kHz and say "nothing to see here- move along". Their THD, power and efficiency numbers have been, continue to be and likely will remain, cherry picked. That is until some authority pulls them up and requires honest disclosure.

But we have more in common than not. Everyone here on ASR is interested in fidelity, music and HiFi gear. Some people come at it a different way than others and place more emphasis on standards and disclosure- others just want to press a button and listen to music. Everyone is different.
I may be mistaken and if so please help me to get a better understanding of the matter.
If what you are explaining about bandwith and distortion is true for amplifiers, why is it not true for a cd player, which is also limited to 22kHz?
And if so, why should an amp have a bandwith 5 times bigger than a cd player, i never heard anybody complain about cd players.

Regards,
Rob.
 

boXem

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I was commenting on the shape of the distortion curve not how the feedback works. That the Hypex amp use multi-pole feedback compensation is well documented. In the distortion graph shown it bulges between c 7 kHz and HF and espec on the higher order harmonics. One of them is at -80 dB which is high in my view for an amp showing single tone ppm level distortion at 1 kHz. This is not the distortion profile of an ultra low distortion amplifier which is how it’s marketed, so I’m simply asking why this is the case.
Hypex Nilai 500 DIY
1677409094197.png


Purifi 1ET400A
1677409146642.png


Took me 2 minutes to find out, copy/paste included...
 

Matias

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And we are repeating ourselves over and over and over...

Edit: I just added Q7 in the Class D FAQ, along with numbering them. Now it is easier to answer: check Q&A 7. :)
 
Last edited:

pma

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Hypex/Purifi et al, just throw all that out the window and draw a line at 20kHz and say "nothing to see here- move along". Their THD, power and efficiency numbers have been, continue to be and likely will remain, cherry picked. That is until some authority pulls them up and requires honest disclosure.

Hi John, this is how the NC252MP measures with 90kHz measuring bandwidth. Spectrum of 1kHz/25W, 20kHz/25W and finally THD+N vs. power at 1kHz, 10kHz, 15kHz and 20kHz, 4ohm load always. This is certainly nothing that one could put into the datasheet, so they had to investigate soft test conditions to make it look better. I will continue posting facts and will prepare more comparisons. Nilai and Purifi probably would not differ much with measuring BW 90kHz.

NC252MP_BW90kHz_THDN_25W4R_1kHz_2.png


NC252MP_BW90kHz_THDN_22W4R_20kHz_2.png


NC252MP_BW90kHz_thdnlevel_1-20kHz.png



Took me 2 minutes to find out, copy/paste included...

BTW I do not believe their datasheets. Soundstage measurements of NAD C298 (Purifi) show very different CCIF distortion level. Hypex also do not say a word about measuring bandwidth and filters used in their measurements. It is close to marketing policy, hiding facts.
 

Rick Sykora

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And we are repeating ourselves over and over and over...

Agree, this is part of why others have accused ASR members of being overly focused on measurements. For that matter, claiming Hypex/Purifi are spinning their specs when most other vendors are doing exactly the same. Not to mention the lack of discussion of whether the measurement differences are audible or not.

This thread's discussion needs to move on or should be closed.
 

Rob Fens

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Hi John, this is how the NC252MP measures with 90kHz measuring bandwidth. Spectrum of 1kHz/25W, 20kHz/25W and finally THD+N vs. power at 1kHz, 10kHz, 15kHz and 20kHz, 4ohm load always. This is certainly nothing that one could put into the datasheet, so they had to investigate soft test conditions to make it look better. I will continue posting facts and will prepare more comparisons. Nilai and Purifi probably would not differ much with measuring BW 90kHz.

View attachment 267676

View attachment 267677

View attachment 267678




BTW I do not believe their datasheets. Soundstage measurements of NAD C298 (Purifi) show very different CCIF distortion level. Hypex also do not say a word about measuring bandwidth and filters used in their measurements. It is close to marketing policy, hiding facts.
Hey John and PMA,

I am deeply impressed by your knowledge about audio, so i hope you can give me an answer regarding my questions in post #468.
Why is a bandwith of 22kHz good enough for cd players and not good enough for an amplifier?

Best regards,
Rob.
 

Shadders

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Hey John and PMA,

I am deeply impressed by your knowledge about audio, so i hope you can give me an answer regarding my questions in post #468.
Why is a bandwith of 22kHz good enough for cd players and not good enough for an amplifier?

Best regards,
Rob.
Hi,
CD is restricted to 22kHz based on the limitations of CD using a sampling frequency of 44.1kHz. The measuring equipment such as Audio Precision will still use 80kHz measurement bandwidth.
Regards,
Shadders.
 

Rick Sykora

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That’s excellent. But the review graphs here don’t seem to show that. Might be Amir needs to add a 19+20 kHz IMD test. I would recommend that for any amplifier - whether class D or linear AB etc

Please see post #429
 

sgshanaf

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As someone who presently has a pair of Nilai mono block kits enroute, I would appreciate knowing why I should care there are perhaps comparable finished amps available in the same price range. Assembling the kits sounds like fun, and shouldn't take long. Is there something about their design as kits that will diminish the finished product, in terms of performance or reliability?
Since the Nilai have built in input buffers there is not going to be nearly as much (any?) variation between prebuilt and kits for the Nilai amps. I suppose someone could replace the power supply, but I've not heard anything bad about Hypex power supplies.

I built a pair of the Nilai mono blocks and have no regrets in going this route.
 

sgshanaf

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I'm new to this forum: does value even properly come into play for product reviews? I don't see how it can. After all, the greatest value in amplifiers is found in the cheapest ones. They take you from silence to music, at the least cost. And probably satisfy the needs of a majority of music lovers (with their smart phones and earbuds). At the other end of the spectrum are folks who spend $1,000/foot for speaker cable because they are not limited by price and are easily persuaded.

Personally, for a review I just want to know how the device measures compared to other products, and what effect those differences might have on how I hear music played through them. I can draw my own (nonlinear) efficiency curves.
It seems like value only comes up when the price to performance ratio is out of whack. Amir seems to only bring up cost when it is far out of line with what you get for it.
 

tmtomh

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As someone who presently has a pair of Nilai mono block kits enroute, I would appreciate knowing why I should care there are perhaps comparable finished amps available in the same price range. Assembling the kits sounds like fun, and shouldn't take long. Is there something about their design as kits that will diminish the finished product, in terms of performance or reliability?

No, no reason for you to care at all. But that's because of your particular perspective, approach to amps, and use-case. Many folks, including many members here, view it conversely: why should they pursue a DIY kit if they can get a pre-built unit with a professionally manufactured case, and often a warranty, for the same price?

Neither approach or perspective is wrong; they're just different, and both totally valid.

I'm new to this forum: does value even properly come into play for product reviews? I don't see how it can. After all, the greatest value in amplifiers is found in the cheapest ones. They take you from silence to music, at the least cost. And probably satisfy the needs of a majority of music lovers (with their smart phones and earbuds). At the other end of the spectrum are folks who spend $1,000/foot for speaker cable because they are not limited by price and are easily persuaded.

Personally, for a review I just want to know how the device measures compared to other products, and what effect those differences might have on how I hear music played through them. I can draw my own (nonlinear) efficiency curves.

Welcome to the forum!

You raise a very interesting point, and your point plays into a lot of the discussion here.

The short response to your question is, of course you are correct: the cheapest amplifier that reproduces signals transparently - that is, with frequency response nonlinearities, noise levels, and distortion levels that are below the ability of humans to hear - is by definition the best value.

Of course, in reality it gets more complicated, because there are other questions that are variable based on individual situations and preferences and are sometimes difficult to quantify precisely, but are in my view still within the overall realm of objective qualities of one sort or another:

1. Build quality/likely longevity of the product;

2. Location company and of available vendors - the more inexpensive the product itself, the more the price comparison can change if one item is available domestically with free shipping while another is only available internationally with expensive shipping; and location of manufacturer can also have a major impact on how practical it is to be able to actually take advantage of the warranty if something goes wrong with the amp; and

3. Watts/power/current capacity - do you get an amp with 4x the power for 2x the price of another, otherwise comparable amp? For folks listening in mid-field with highly efficient speakers, the answer is probably No. For folks listening far-field with less-efficient speakers, the answer might be Yes.

Finally, there's the more subjective issue of how a product makes us feel. The science/measurements/engineering ethos of this forum is still an ethos - it still speaks of values that folks bring to their evaluation of products. So having extra power reserves, first-rate build quality, "extra padding" in the performance specs beyond the threshold of audible transparency, and so on - these are things that many folks here like to see in products they consider buying.

Periodically some folks will comment here in threads accusing all of ASR of being a sham or hypocritical because "everyone here chases specs" even when better specs don't make an audible difference, and therefore we are allegedly no different from people who seek out cable lifters, high-end interconnects, and other audiophile "tweaks" even when they don't make an audible difference. The claim is that all this stuff is irrelevant and just makes us feel better, and so therefore measurements are the same thing as snake oil. It's not true of course, but like many bad arguments that refuse to die, it's just close enough to the truth to be misleading.
 
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Skeeter

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Seems to me this might be what’s going on here:-

1.The loop gain is VERY high (rough guess 100 dB or more) and the multi-pole compensation suppresses distortion in the audio band up to 20 kHz to very low levels
2. This will also provide very good in-band IMD performance which is clearly evident from boXem’s post above.
3. Above 20 kHz, the loop gain drops off very rapidly as it has to in order to get to close the loop at some reasonable unity loop gain frequency, say 1-3 MHz’ at 20 dB/decade enduring adequate phase margin.
4. So the loop gains above 20 kHz drop off dramatically and that’s why the wide band (90 kHz) HF distortion seem to be higher than one would anticipate looking at the in band distortion performance.
 
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