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SMSL M500 DAC Only “Thermal Issue” not “Golden Sample”

WolfX-700

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#1
When I started publishing measurement results in ASR, I said that part of my work would be devoted to "double checking" on Amir's measurement results. To avoid a situation where a vendor sends a "golden sample" to ASR

Of course, this part of my work depends on luck. The key is the equipment my friends can provide me, or whether the equipment I buy is measured by Amir.

Amir and I got results within a margin of error in a longer measurement. We followed basically similar temperature conditions and the end results were similar. But the trend is reversed. (The SINAD I have on hand goes up, while Amir's THD + N gets worse). You can see pages 4 and 5 of this post.


At present, the probability of "golden sample" issues is decreasing, while the probability of "thermal issue" is higher.

I have placed an order for a new unit. Please stay tuned.

2019/12/11 Update:
I received the unit I purchased.

BuyR.jpg

Dashboard(Cold room temp=72℉ ):
NewDash.jpg


Long-term testing:At the time I marked, I attached a warm pad to the M500 and covered it with clothes.
Heat2.png

IR.jpg


HeatD.png



The final measurement results match Amir's earlier measurements! It can be considered that the M500 is only an issue in which the measurement result changes greatly with temperature changes.

There is no "Golden Sample"




Just today, I received a SMSL M500 from a friend.

Photo.jpg



After measurement, I think this is a big problem ... because the measurement results are very different from Amir.

Here are the measurements:

Dashboard.jpg



Dynamic-Range---AES17.jpg
Linearity-(-20.jpg
SMPTE-Ratio.jpg
Multitone.jpg

Jitter.jpg



I think I used the same settings as Amir (ASIO4ALL USB 48K, Volume Set to 34 4V Out)

But the measurement results are very different from @amirmhttps://www.audiosciencereview.com/forum/index.php?threads/smsl-m500-dac-and-hp-amp-review.9606/

So if there is a chance, I think Amir can try to get another M500 from a third party channel.

I will also try to find another one.

If the "golden sample" is confirmed ...


Update :

Just now I read Amir's post carefully. It was found that his dashboard was using a sampling rate of 44.1KHZ.

To avoid controversy, I did another quick measurement with 44.1KHZ.

Here are the results:

441XLR.jpg
441RCA.jpg
 
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Veri

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#3
When I started publishing measurement results in ASR, I said that part of my work would be devoted to "double checking" on Amir's measurement results. To avoid a situation where a vendor sends a "golden sample" to ASR

Of course, this part of my work depends on luck. The key is the equipment my friends can provide me, or whether the equipment I buy is measured by Amir.

Just today, I received a SMSL M500 from a friend.

View attachment 41653


After measurement, I think this is a big problem ... because the measurement results are very different from Amir.

Here are the measurements:

View attachment 41656


View attachment 41657 View attachment 41658 View attachment 41659 View attachment 41660
View attachment 41662


I think I used the same settings as Amir (ASIO4ALL USB 48K, Volume Set to 43 4V Out)

But the measurement results are very different from @amirmhttps://www.audiosciencereview.com/forum/index.php?threads/smsl-m500-dac-and-hp-amp-review.9606/

So if there is a chance, I think Amir can try to get another M500 from a third party channel.

I will also try to find another one.

If the "gold sample" is confirmed ...
SINAD, linearity, multitone and jitter are still decent. But how did they revert to IMD hum ????

Output stage must be different. @WolfX-700 can you test at maximum volume? Is performance same? Or worse still?

In any case this re-test is very valuable, looking at this: Sabaj D5 and Topping DX7Pro are better in objective performance. Thank you,
 
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WolfX-700

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#5
SINAD, linearity, multitone and jitter are still decent. But how did they revert to IMD hum ????

Output stage must be different. @WolfX-700 can you test at maximum volume? Is performance same? Or worse still?
Take a quick measurement before going to supper:

MAX Volume SINAD = 109
 

mi-fu

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#9
Wow. I didn't expect that!!!

I think measuring a third (random) sample will be important.
 

WolfX-700

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#15
Regardless of the conclusion on this particular case, relying on the companies is already a significant risk that the tests will be biased.
I don't think it's possible to completely avoid the situation where companies provide samples.

Many times, reader samples are not always readily available.

If possible, ASR can introduce a red and yellow card system for companies.

If you repeatedly find that the sample provided by the company is very different from the actual retail. Make certain marks or do something else ...
 
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MusicNBeer

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#16
Regardless of the conclusion on this particular case, relying on the companies is already a significant risk that the tests will be incorrect.
Agreed. I'm no longer going to put any weight into the review unless it's a random production unit being tested.
 

mi-fu

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#17
Agreed. I'm no longer going to put any weight into the review unless it's a random production unit being tested.
Well.. we need enough members to send in samples to measure (it means they need to purchase it before seeing any measurement). And sometimes people want to have early (pre-production) measurements before making their purchase decision.

There is no perfect solution :)
 

JohnYang1997

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#18
Well.. we need enough members to send in samples to measure (it means they need to purchase it before seeing any measurement). And sometimes people want to have early (pre-production) measurements before making their purchase decision.

There is no perfect solution :)
Generally I don't think this would be an issue. If one manufacturer does this, the whole forum will be very cautious about this manufacturer. The reputation would suffer.
 

WolfX-700

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#19
Generally I don't think this would be an issue. If one manufacturer does this, the whole forum will be very cautious about this manufacturer. The reputation would suffer.

Yes, it may be a separate incident. I have recorded the serial number of this M500 and I will try to find another M500 for testing.

It would be a shame if SMSL did send a golden sample.
 

Jinjuku

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#20
I personally wouldn't accept a company provided unit. If a manufacturer wants a unit benched allow for an in the wild unit to be purchased and the company reimburses or they provide pre-payment for one to be obtained.

It's what Consumer Reports does.
 
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