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Review and Measurements of Sabaj D5 DAC & Amp

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amirm

amirm

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Thread Starter #122
@amirm can Gustard U12 make the jitter test of Sabaj D5 better?
I would have to measure other inputs to see if they are better. It is possible the jitter is internally generated.
 

KSTR

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Wow, I haven't seen those. For what I know most companies like those just got dscopes. What about the software part of that thing? Similar to original?
DScopeIII is also widely used both for lower price and much easier user interface compared to all AP System 1 and System 2 models (in the APX models they finally fixed this). But since AP is the industry standard it seems obvious that companies whish to have one, for generating industry standard plots and last not least, as a status symbol. Sometimes they are there to show off only and not used to really do some work with them (same thing I'v seen with expensive Klippel speaker test systems gathering dust).

For software side, I had used my personal laptop with the original AP2700 control software and it run without any problem.
This is really puzzling, I have no idea what's actually going on and if that machine really was a true clone wrt to hardware and firmware (that would be really hard to do) of if it just was, at least partly, a relabelled original made from spare/refurbished parts or something....
 

peterwen

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The US-$ 25k one? I doubt it. But I may be wrong. The Khadas folks do, that was the 1st time I thought this site shouldn't just double check their measurements on the same machine.

Both Khadas and Sabaj sent the items in, it was not someone "discovering" them. It is not the right "ethic". Edit: But it would be ethical if they paid (significantly) for maintenance the site if they want to doublecheck their measurements.
Understand your doubts, but the other manufacturer like Topping and Okto also have sent the product to measurement. Your question should not be directed only to this product.
I hope more manufacturers send products for review and measurement, more data will give us more comparisons. This allows us to "notice" it. And thanks for what Amir have done.
 

Nango

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Understand your doubts, but the other manufacturer like Topping and Okto also have sent the product to measurement. Your question should not be directed only to this product.
I hope more manufacturers send products for review and measurement, more data will give us more comparisons. This allows us to "notice" it. And thanks for what Amir have done.
I still don't see the added value for them and for us to double-check their AP measurements at ASR other than seeking publicity and higher sales. Amir said he is fine with that so that's ok then.

If you want to check the emissions of your brand new Q7 and you use the same test equipment than Audi uses in it's factory you are just repeating the measurement and the results can't be other than identical. I don't see where this is excellence.

Only using a different test equipment or even a different methodology will reveal any anomalies in their measurements and results, if there were any.

ASR will end up "testing" only gear that has been already tested 3 days before with same equipment as all the other mfr with no access to the AP obviously won't send in anything.
 
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Krunok

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If you want to check the emissions of your brand new Q7 and you use the same test equipment than Audi uses in it's factory you are just repeating the measurement and the results can't be other than identical. I don't see where this is excellence.
Well, that is a really good example but unfortunately it disproves what you're saying. The point is that with measurements being done by indpendent party you sometimes get different results then measurements done by manufacturer, and that is exactly what happened in "dieselgate" affair. Although the same equipment was used independent measurements showed that emmision figures declared by manufacturer differ by quite a lot from those done indpendently. A really good example to learn about the value of independent measurement. ;)
 

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No, the (european authorities) were not "independent" until they used a different equipment than the mfr (they were using all the same equipment and same methodology, provided by Bosch, no wonder results were ok during ages). That's the point.

When the U.S. started measuring under different circumstances they started getting the clue.

But hey, issue is cleared to me. So let's get back to the gears.
 

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No, they were not independent until they used different equipment than the mfr. That's the point. When the U.S. started measuring under different circumstances they started getting the clue.
Did they? Or was it due to the diesel engine calibration parameters in the ECUs which recognised that emmision was been measured on roller wheels so they optimised engine parameters to generate emmisions which were impossible to get on the road driving? Folks in U.S. measured the same way (on the roller wheels) but then they compared those measurments with measuremens taken on the road. Affter that it was easy to conclude the manufacturers were cheating.
 

Nango

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Exactly, the U.S. changed methodology. They didn't rely on the tales provided by Bosch.
 

Krunok

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Exactly, the U.S. used different methodology. They didn't rely on the tales provided by Bosch.
The point is not on the methodology, but on the fact it was done independently of manufacturer. Measuring emmissions on the road instead of roller wheels is something manufacturers have also done but they choose to hide them and to cheat. It was discovered because another measurements were taken independetly of manufacturers, not because some new measurement method was used.
 

Nango

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European authorities are supposed to be independent and measured wrong during many years until the US told them how to measure well.
 

Nango

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If ASR uses the same equipment and the same methodology to "test" whatever product has been sent in by let's say Sabaj or whoever, the only thing ASR is certifying is that Sabaj, 1) yes, they read the AP manual and, 2) yes, they can handle the AP, [Edit:] or, alternatively, 3) they paid someone who read the manual and can handle the AP.

The good or bad results the gear obtained is nothing new, that was already done by them. There is nothing "Excellent' with that (other than merely double-checking).

If this is the mission of ASR, that's ok, and I was wrong.
 
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helloworld

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If ASR uses the same equipment and the same methodology to "test" whatever product has been sent in by let's say Sabaj or whoever, the only thing ASR is certifying is that Sabaj, 1) yes, they read the AP manual and, 2) yes, they can handle the AP.

The good or bad results the gear obtained is nothing new, that was already done by them. There is nothing "Excellent' with that (other than merely double-checking).

If this is the mission of ASR, that's ok, and I was wrong.
Then why other companies like sony or schiit, they have AP, but did not design a DAC with thd+n 119dB?
 

JohnYang1997

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If ASR uses the same equipment and the same methodology to "test" whatever product has been sent in by let's say Sabaj or whoever, the only thing ASR is certifying is that Sabaj, 1) yes, they read the AP manual and, 2) they can handle the AP.

The good or bad results the gear obtained is nothing new, that was already done by them. There is nothing "Excellent' with that (other than merely double-checking).

If this is the mission of ASR, that's OK.
Do you know what measurements are done here? Is there imd graph in the spec? Is there distortion of different loads for headphones output? Is there distortion vs frequency? Is there distortion vs power? Is there j-test graph? Tested by same equipment doesn't mean we get the same set of measurements. Have you ever measured anything, do you even know what these measurements mean? Did you even read the measurements?
 

JohnYang1997

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If ASR uses the same equipment and the same methodology to "test" whatever product has been sent in by let's say Sabaj or whoever, the only thing ASR is certifying is that Sabaj, 1) yes, they read the AP manual and, 2) yes, they can handle the AP.

The good or bad results the gear obtained is nothing new, that was already done by them. There is nothing "Excellent' with that (other than merely double-checking).

If this is the mission of ASR, that's ok, and I was wrong.
Plus there are companies like audio-gd who has published ap graphs which shows superb performance but turn out to be worse than apple dongle.
 

Krunok

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If ASR uses the same equipment and the same methodology to "test" whatever product has been sent in by let's say Sabaj or whoever, the only thing ASR is certifying is that Sabaj, 1) yes, they read the AP manual and, 2) yes, they can handle the AP.

The good or bad results the gear obtained is nothing new, that was already done by them. There is nothing "Excellent' with that (other than merely double-checking).

If this is the mission of ASR, that's ok, and I was wrong.

Did it ever occur to you there is a 3rd option ASR is also testing?

3) yes, they published correct results

You don't seem to understand that one fo the purposes of independent testing is to verify the figures published by manufacturer.
 

Nango

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Plus there are companies like audio-gd who has published ap graphs which shows superb performance but turn out to be worse than apple dongle.
Never heard audio-gd measured on AP and published AP figures. In these cases ASR is using different equipment.

Whenever a Mfr claims having used the AP let them announce it on a new section in this forum. And as long it is not accompanied by a certificate from a 3rd party it will be as saying nothing. And if it is a certificate by ASR let them pay high for that to Amir or to the site. Any other 3rd independent institute would charge them anyway.

And all other not using AP for checking the designs let them get checked here, as before.

But I understand that ASR sees this different and that's ok.
 

Nango

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Did it ever occur to you there is a 3rd option ASR is also testing?

3) yes, they published correct results

You don't seem to understand that one fo the purposes of independent testing is to verify the figures published by manufacturer.
If one Mfr is cheating and publishing wrong AP results, .....I mean, such a behaviour will happen only once if it wasn't a (big) mistake. After a 2nd "mistake" this Mfr is done, similar to what happens now to Shiit.
 
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