Hypex NCx500 Class D Amplifier Review

[pma]

Thank you for the twin tone posted. The result is very good.
All the distortion methods do test different attributes of amp nonlinearity. Twin tone is about dV/dt and the result stays in audio band. d2H would be high again, but it is not investigated in case of 22kHz BW.

 

[pma]

The point is this twin tone tells us far more about sound quality than SINAD. Yet it’s only included in the Benchmark review. I can imagine the reason why is John insisted on Amir providing it. As he understands how important the measurement is in regards to sound quality.

I know that the HF twin tone tells us more. It is my favorite test method - in many threads shown, here. However, @amirm does not consider it important. I have given up persuading him to use it. He says it is unimportant.

 

[BR52]

The point is this twin tone tells us far more about sound quality than SINAD. Yet it’s only included in the Benchmark review. I can imagine the reason why is John insisted on Amir providing it. As he understands how important the measurement is in regards to sound quality.

Did he insist?

 

[BR52]

There’s likely a reason why the Benchmark amp review is the only review that has this important data shared. Because John is a professional who understands what matters.

this is not the answer of my question.

 

[BR52]

I have no idea about conversations that go on behind the scenes. But manufacturers often request certain measurements be preformed to demonstrate the performance of their products.

Now I have a clear picture about your posts.
Thanks

 

[mdsimon2]

I have no idea about conversations that go on behind the scenes. But manufacturers often request certain measurements be preformed to demonstrate the performance of their products.

Looks like our favorite Canadian troll is back. How is it going Mike aka @Mivera @Amplifier dude? Slightly different tack this time but man you just can’t stay away.

Michael

 

[BR52]

First I’m a Hypex employee, now I’m someone else. Hmmm wonder who I’ll be next!

We like your fact and knowledge based discusions.

 

[GXAlan]

We all who are involved in measurements know that any class D amplifier (up to nowadays) has dirty nasty spectrum just above 22kHz and that there is no proof that spectrum components will not intermodulate in tweeters, resulting in audible frequencies. Marketing departments need to demonstrate nice plots so they speak about necessity to limit the measuring BW to 20 or 22 kHz.

This is pretty clean to 40 kHz and the Panasonic UB9000 feeding it wasn’t the cleanest source either.

This is of course a Marantz buffer with bridged NC500OEMs.

I will try to run some extra tests today if I have time.

 

[pma]

View attachment 257487

This is pretty clean to 40 kHz and the Panasonic UB9000 feeding it wasn’t the cleanest source either.

This is of course a Marantz buffer with bridged NC500OEMs.

I will try to run some extra tests today if I have time.

Good. Please try higher base frequency and power >100W. Not 5W. I wonder if you would not see sudden noise floor abrupt raise at some point above 100W.

 

[BR52]

Good. Please try higher base frequency and power >100W. Not 5W. I wonder if you would not see sudden noise floor abrupt raise at some point above 100W.

Saturation of the output inductance?

 

[Rottmannash]

Please ignore restorer-john. He does not speak for most of us on this forum and is well known to have an anti- Class D crusade. He "loses no sleep" but is consumed by preaching against an amplifier technology lol. This seems to be going on for years!
I would rather read your inputs/comments about your products. I still have ucd modules running strong all these years later.

Agreed

 

[pma]

The point is this twin tone tells us far more about sound quality than SINAD. Yet it’s only included in the Benchmark review. I can imagine the reason why is John insisted on Amir providing it. As he understands how important the measurement is in regards to sound quality.

I like the Cordell triple tone test. And I like it clean in ultrasound region.

 

[BR52]

I like the Cordell triple tone test. And I like it clean in ultrasound region.

View attachment 257491

Hopefully you can hear it.
I am happy with good measurements max to 20 -22 kHz

 

[pma]

Yes clean above 30kHz is important for cats, dogs and bats. But information above 20kHz doesn’t exist on any audio recordings. Even if we could hear it, and our tweeters could play it. It’s less important to me that audible bandwidth performance.

Hopefully you can hear it.
I am happy with good measurements max to 20 -22 kHz

Intermodulations, guys. Intermodulations in tweeters (and in human ear, if the signal gets in).

 

[BR52]

Hopefully you can hear it.
I am happy with good measurements max to 20 -22 kHz

and before I forget no DC.

 

[BR52]

Today I'm out.

 

[goryu]

Looks like our favorite Canadian troll is back. How is it going Mike aka @Mivera @Amplifier dude? Slightly different tack this time but man you just can’t stay away.

Michael

Spotted that as well right away...

 

[AdamG]

Looks like our favorite Canadian troll is back. How is it going Mike aka @Mivera @Amplifier dude? Slightly different tack this time but man you just can’t stay away.

Michael

Looks like you were correct and thanks for bringing this to our attention. Good catch Sir!

It was him and this new account is now closed.

 

[BossBunos]

If the SINAD leaderboard is indeed intended for just finished products then yes I agree, please do remove all modules on there. including our NC400, the Purifi module. Just all. We don't make the SINAD leaderboard. that is up to Amir. We don't care. We certainly do not manipulate or try to distort your discusions. We do not appreciate such comments and will prevent us participating such forums. So be carefull were you point your finger to. thanks.

To be clear: as soon as we release a new module, OEM or DIY, you readers and contributors on this forum immediately request test results from Amir. As we have nothing to hide we are more the happy to issue samples to Amir for this purpose. But it seems completely irrelevant to most of you that it is or isn't available for DIY customers. but then complaining the use of the module is irrelevant to normal use case. very strange.

I don't think it's a finger pointing to hypex. More a debate on what the sinad ladder should be used for. As a reader of this forum it would be nice to compare apples to apples (same gain for power amps) when the sinad is compared.
Personally I love the work Amir is doing and what hypex is providing for/to the audio community.
I can't speak for other people but sometimes we are passionate and dig into those measurements that we forget to show our appreciation for the effort that is put into it by amir and the manufacturers. So just to be clear: Thank you amir and hypex

 

[Stinius]

Intermodulations, guys. Intermodulations in tweeters (and in human ear, if the signal gets in).

Exactly right.