restorer-john
Grand Contributor
It adds an hour to every review. Ouch. But in real terms, it should be a pre-requisite before testing.
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SMSL M500 DAC Only “Thermal Issue” not “Golden Sample”
- Thread starter WolfX-700
- Start date
It adds an hour to every review. Ouch. But in real terms, it should be a pre-requisite before testing.
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I don't listen to music after waiting one hour.
restorer-john
Grand Contributor
You're missing the point. All equipment should be tested at typical stabilized operating temperature.
With many of these PCBs in a sealed box, spot temperatures will elevate, sometimes enough to cause issues.
What's the hw version of the one amir measured?
Also can we have a teardown comparison?
Also can we have a teardown comparison?
OP
- Thread Starter
- #87
This is a unit from my friend ... I must get permission to teardown
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The sinad is getting better as the unit warms up so it appears there's a difference beyond test temperature.
Is there really a 2dB difference in SINAD between the two channels? Is it due to noise or distortion?
alright
OP
- Thread Starter
- #91
So I used the word "Probably "
And I also ordered another unit. I also hope this is just a "bad unit" and not a manufacturer's credibility issue.
It's 8:10am here in Sydney. I just woke up...
renaudrenaud
Major Contributor
Ha sorry Wolf, it was not for you but in general. Have a good night.
Tks
Major Contributor
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It would be good for us to know in the test. But would be disaterous if manufacturers were outputting hardware revisions with no indication.
bequietjk
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And yours for only $87,000. Beeswax and wombat pee fuse $8k extra.
restorer-john
Grand Contributor
Why do people say "teardown"? It's such a brutal word and suggests irreversible damage, stripped screws and broken chit.
Carefully dismantle would be an easier sell to your friend.
Ok, after 2 hours of soak time, this is what I got:
We have a degradation of 5 to 6 dB depending on channel. Note that the above is highly zoomed in covering only 10 dB of range.
I then re-rand the FFT in the dashboard:
We have very good matching of the distortion order/level. Second and third harmonic are right on the money.
The noise level is lower in mine but that is affected by FFT parameters.
Looking at dashboard sinad, I see:
This is versus 110 in L7's tests. This is within what I consider acceptable given different analyzers, units, etc.
In summary, large amount of difference is due to thermal conditions, not any hand selection of a unit/components.
We have a degradation of 5 to 6 dB depending on channel. Note that the above is highly zoomed in covering only 10 dB of range.
I then re-rand the FFT in the dashboard:
We have very good matching of the distortion order/level. Second and third harmonic are right on the money.
The noise level is lower in mine but that is affected by FFT parameters.
Looking at dashboard sinad, I see:
This is versus 110 in L7's tests. This is within what I consider acceptable given different analyzers, units, etc.
In summary, large amount of difference is due to thermal conditions, not any hand selection of a unit/components.
IMD hump?
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