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

[mi-fu]

Thanks for your hints：

HW1.5 SW1.2

Warming up is a good idea ... In fact, I have warmed up for about 2 hours before measuring ...

Then ... Now it's about 6 hours of continuous operation ...




View attachment 41676

it gets noisier after 6 hours of operation??!!

 

[amirm]

I could order a unit from Amazon and drop ship to Amir.

Thank you very much. That is very kind. But this one is on me to resolve. So I just purchased one with Prime shipping so we know stock is here in US (so can't be changed by the company) and will get to me soon.

 

[half_dog]

Ooh no x.x

 

[WolfX-700]

Thank you very much. That is very kind. But this one is on me to resolve. So I just purchased one with Prime shipping so we know stock is here in US (so can't be changed by the company) and will get to me soon.

Thank you for your reply and decision to remeasure. I think the credibility of the manufacturer is important.

 

[pozz]

There's the issue of manufacturing tolerances. How much out of spec is a unit allowed to get before it's considered ready for sale?

 

[Reddy]

Thanks for your hints：

HW1.5 SW1.2

Warming up is a good idea ... In fact, I have warmed up for about 2 hours before measuring ...

Then ... Now it's about 6 hours of continuous operation ...




View attachment 41676

I propose in the future to test the long time stability
Probably a tcr drift

 

[amirm]

There's the issue of manufacturing tolerances. How much out of spec is a unit allowed to get before it's considered ready for sale?

At the minute levels of distortion and noise we are measuring, there is going to be some variations. Here is the SMSL's own measurements:

While their SINAD is similar to mine, the spectrum of FFT harmonics is different.

 

[amirm]

Warming up is a good idea ... In fact, I have warmed up for about 2 hours before measuring ...

Oh. How does it measure before that 2 hour warm up?

 

[DuxServit]

“Beware of Strangers Manufacturers bearing gifts”

 

[WolfX-700]

Oh. How does it measure before that 2 hour warm up?

I played 2 hours of music first ...

I just ordered one. Let's check together how much the deviation is.

 

[amirm]

I played 2 hours of music first ...

I am saying test it COLD. Please turn it off and put it in the fridge to cool off and then re-test. My testing is after a few minutes of warm up, not 2 hours. If this is a thermal issue, we need to figure this out before running down the path of buying other units, worrying about golden samples, etc.

 

[WolfX-700]

I am saying test it COLD. Please turn it off and put it in the fridge to cool off and then re-test. My testing is after a few minutes of warm up, not 2 hours. If this is a thermal issue, we need to figure this out before running down the path of buying other units, worrying about golden samples, etc.

OK I immediately turned off this unit. I will take the measurement after half an hour.

 

[mi-fu]

I played 2 hours of music first ...

I just ordered one. Let's check together how much the deviation is.

View attachment 41677

better hide all the details. otherwise they might send you another "golden copy"!!

 

[Veri]

Great things going on here in this thread

Thanks!

 

[Jinjuku]

Miska is a fan of TIM testing. What is the benefit of a multi-tone vs single tone?

 

[Tks]

I am saying test it COLD. Please turn it off and put it in the fridge to cool off and then re-test. My testing is after a few minutes of warm up, not 2 hours. If this is a thermal issue, we need to figure this out before running down the path of buying other units, worrying about golden samples, etc.

I hope that fridge request was made in jest..

 

[amirm]

I hope that fridge request was made in jest..

It was not. I wanted to make sure the unit starts cold since he has had it running for a while.

 

[amirm]

OK I immediately turned off this unit. I will take the measurement after half an hour.

Thanks. Meanwhile I am testing mine starting from cold and measuring THD+N once a second to see if I can replicate your scenario.

 

[Tks]

It was not. I wanted to make sure the unit starts cold since he has had it running for a while.

I get why you would want to make sure its cold, but I think letting it sit for something like 15 minutes to an hour should suffice. We don't want condensation or thermal shock being an issue after it's taken out from the fridge of all places. It'd be interesting to see what effect temperature has on devices (but that would require testing it while it's in the fridge). You can go to extremes making demonstrations of these sorts of ordeals. But the normal testing from room-temp I think is fine enough for the sake of sanity (unless you want to explore this on all devices going forward, and see what sorts of designs are insulated from these thermal fluctuations over time).

 

[amirm]

I get why you would want to make sure its cold, but I think letting it sit for something like 15 minutes to an hour should suffice. We don't want condensation or thermal shock being an issue after it's taken out from the fridge of all places. It'd be interesting to see what effect temperature has on devices (but that would require testing it while it's in the fridge). You can go to extremes making demonstrations of these sorts of ordeals. But the normal testing from room-temp I think is fine enough for the sake of sanity (unless you want to explore this on all devices going forward, and see what sorts of designs are insulated from these thermal fluctuations over time).

Condensation on a closed device like this is not an issue especially if the unit is immediately turned on once you pull it out of the fridge. I have done such tests in both fridge and freezer.

Anyway, the other important reason I asked him to cool his off in the fridge is that my sample was in our attic which is about 45 degrees F. Wanted him to start with the same baseline as opposed to 70 degree or whatever his room temp is.