strange SMSL M500 high 3rd harmonic

[MusicNBeer]

Interesting point.
I picked up somewhere on this website that 38 would be a good volume level in RCA DAC only mode because it is closest to 4(?) Volts output?
So now you are recommending to turn it down to somewhere between 20 and 30 to achieve transparent results?
(Just for my understanding - by "transparent" you mean that the SINAD is high enough so that decoding errors are outside the audible spectrum?)

Yea, earlier advice was assuming correct behavior from the DAC. At this point, lower is better, at least down to 20 or so.

 

[JSmith]

retest their SU-9

@amirm If you happen to have an SU-9 still I'd really appreciate if you could measure for this. I've just ordered one due to a good price, however will cancel the order before it ships if the SU-9 displays this problem. It's a hassle to pay for return shipping from here, so would probably have to take a loss on it and sell it on.

I will try to contact SMSL

Thanks to both of you.



JSmith

 

[jruser]

What's the theory about why this happens? Something wrong in the analog part of the circuit?

 

[JSmith]

I would just cancel it right away

I've spent months deciding on which DAC's I was interested in, finally saw a good price and took the dive. Feeling a bit bummed now as am expecting it to be a well performing unit. The SMSL M500 had thermal issues, whereas the SU-9 doesn't... I doubt it would be all ESS9038PRO DAC chips and wonder if it is this previously noted thermal issue that may be causing this?

Would be great to verify this issue is only the M500.



JSmith

 

[JSmith]

And you shouldn't choose product by blindly trusting amir's review.

I don't... which is why I just said the decision was made over months, not overnight. I think I've read everything possible about the SU-9.

Use your critical thinking when making a decision.

I do and appreciate this thread, however no need to question my thinking... there was nothing to indicate an issue with this product and it had also been tested here and elsewhere. At this stage there is nothing to indicate that the SU-9 has this issue apart from similarities you mentioned. It needs to be confirmed urgently.

So you're definitely testing V2 of the M500's?



JSmith

 

[liu]

So you're definitely testing V2 of the M500's?

of course.

 

[JSmith]

@SMSL-Mandy or @SMSL_Liu are either of you able to comment or provide some feedback on this please? Happy for you to PM me if required.

I note the Liu account has not been used since May 2020... however I assume being a very common name the OP @liu is a different person.

Edit: Oh hey that was my 500th post here... it seems I'm no longer a Senior Member, however now am addicted to fun and learning.



JSmith

 

[liu]

@SMSL-Mandy or @SMSL_Liu are either of you able to comment or provide some feedback on this please? Happy for you to PM me if required.

I note the Liu account has not been used since May 2020... however I assume being a very common name the OP @liu is a different person.

They reached out to me this morning and we had a few discussions. All I can tell you is, now they become very promptly. They are currently investigating the issue, starting by getting Prof. Wolf's device [because it's in China and can be easily transferred to their company] and analyzing what's going on. I think they will share what's going on when they have more data.

Yes Liu is a very common name in China. according to this, "As of 2019, Liu is the fourth most common surname in China. If you're a Liu, you share the same last name as nearly 70 million people – over the entire population of France, the United Kingdom, even Thailand!"

 

[JSmith]

we had a few discussions

Good... did they happen to agree with you that this issue may be present in other SMSL products such as the SU-9 or did they suggest this is unlikely?

Much of their product information includes measurement graphs from an analyser...



JSmith

 

[WolfX-700]

They reached out to me this morning and we had a few discussions. All I can tell you is, now they become very promptly. They are currently investigating the issue, starting by getting Prof. Wolf's device [because it's in China and can be easily transferred to their company] and analyzing what's going on. I think they will share what's going on when they have more data.

Yes Liu is a very common name in China. according to this, "As of 2019, Liu is the fourth most common surname in China. If you're a Liu, you share the same last name as nearly 70 million people – over the entire population of France, the United Kingdom, even Thailand!"

SMSL attaches great importance to this matter, and I have sent the samples I obtained to SMSL. At the same time SMSL also sent out their sample (new) to me. There is an embarrassing situation---I arranged a tour from April 30th to May 4th...I will update the information as soon as possible!

 

[JSmith]

At the same time SMSL also sent out their sample (new) to me. There is an embarrassing situation---I arranged a tour from April 30th

Chances of it arriving before you leave? You don't have an SU-9 do you?

May 4th

May the Fourth be with you.



JSmith

 

[WolfX-700]

Chances of it arriving before you leave? You don't have an SU-9 do you?

May the Fourth be with you.



JSmith

I asked SMSL to lend me a SU-9 for verification while sending me the new M500. They agreed...but I think it may take after May 4th...

 

[Veri]

I asked SMSL to lend me a SU-9 for verification while sending me the new M500. They agreed...but I think it may take after May 4th...

Thanks for your efforts, Wolf!

 

[TheTalbotHound]

@amirm , now that Prof. Wolf successfully reproduced this,
I guess all 9038Pro DACs produced by SMSL have the same problem.
You really need to retest their SU-9. Might be very broken.

Has wolf done a first test of it? Either way whether it is a first test or a retest that device should certainly be put through some tests just to be sure.

 

[jruser]

I was about to buy an SU-9 and SP400. I give up with the constant SMSL problems and revisions. Ordered another 887 and a D70s instead.

 

[Jimbob54]

Kind of a

Interesting point.
I picked up somewhere on this website that 38 would be a good volume level in RCA DAC only mode because it is closest to 4(?) Volts output?
So now you are recommending to turn it down to somewhere between 20 and 30 to achieve transparent results?
(Just for my understanding - by "transparent" you mean that the SINAD is high enough so that decoding errors are outside the audible spectrum?)

34

 

[jani80k]

Kind of a
34

That is the "new" recommendation for the M500 ?

 

[Jimbob54]

That is the "new" recommendation for the M500 ?

No. 34 is closest to 4v. Not a recommendation for anything other than getting close to 4v output on xlr. In the original version amir tested.

 

[MusicNBeer]

That is the "new" recommendation for the M500 ?

No, the recommendation is as low as you can go, 30 or below. Preferably 20.

 

[lucadoc]

No. 34 is closest to 4v. Not a recommendation for anything other than getting close to 4v output on xlr. In the original version amir tested.

If I have well understood the preamp section of this Dac is not so transparent or at list not so "resolutive" (forgive my bad English) when you lower the volume as there's not a fixed Dac position.

Now we are in the middle of a problematic situation : decrease the volume to avoid distortion or increase the volume to maintain the full resolution? Which is the lesser of evils?