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SMSL D-6s Balanced DAC Review

Rate this DAC:

  • 1. Poor (headless panther)

    Votes: 11 2.4%
  • 2. Not terrible (postman panther)

    Votes: 6 1.3%
  • 3. Fine (happy panther)

    Votes: 28 6.1%
  • 4. Great (golfing panther)

    Votes: 411 90.1%

  • Total voters
    456
Hello everyone,

starting on page 52, Kosmonaut reports on an update for the DAC. Shenzhenaudio send me the firmware update "SMSL D-6S_MCU v1.2_EN_241008.exe". However, they haven't answered my question about what the update actually does.

Does anyone have any information or at least an idea? I wouldn't perform the update unless absolutely necessary or at least if there's some benefit to it.

Best regards
 
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Don't know for sure. But based on the differences in the paper and online manuals, at least the filter preset numbers where changed. Or could be just bug fixes. Updating is tricky because the unit doesn't have a hard power switch, and the update program needs the unit to be powered on within a window of a few seconds. So you need to click update and physically plug in the power supply cable within that short window.

The update program does interface over the USB cable when the power cable is disconnected though, but the power needs to be plugged in when the actual update starts. The firmware and instructions are in English on Shenzhen Audio's website. SMSL's website only has the Chinese version. The English instruction grammar isn't the best and the subtly of power-on window timing isn't clearly articulated.
 
Thank you very much. I don't really see the need for an update. My device is working perfectly. If the update only rearranges some inaudible filters, I can easily do without it. The risk of damage isn't worth it.
 
I agree, don't update unless you need to. The first and second time I tried to update it, it seemed to fail - based on the Chinese flashing program output; but the unit still worked.

Again, I couldn't tell because it was in Chinese. But it didn't brick the unit.

The fourth flash with the Chinese program worked. I'm basing this on the results compared to the instructions.

When I found the English flash program on Shenzen's website, I reflashed again just in case, and it then totally agreed with the instructions.

I tend to over sample now, so I don't really care about the filters. Nor do I use bluetooth or DSD... Just need toslink or USB to work for PCM.

Also, with the USB driver, and through my SH-9, the sample rate change "pop" is more like a low volume puff. Not an issue at all. Always-on driver streaming works.
 
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Hello! can someone pls send me the real firmware 1.1
I can only download from their official website, they said 1.1 but it actually v1.2_EN_241008 :(
 
Hello! can someone pls send me the real firmware 1.1
I can only download from their official website, they said 1.1 but it actually v1.2_EN_241008 :(
I just checked the files I used. The folder is called "SMSLD6SMCUFWV101" and it contains a file suggesting v1.2 like stated by you: "SMSL D-6S_MCU v1.2_241008"

I remember that I came across this (completely unnecessary) inconsistency back then. According to the folder on my NAS I downloaded this FW mid of Nov. 2024.

I cannot say for sure, but I'm quite sure that I used that file to update my D-6s.

Is there an indication that there's something wrong with this firmware?

There's a thread addressing the wrong labeling of the PCM filters - eventually you may find more information there.
 
A couple of questions, maybe owners of this DAC have some info for me.

Does this DAC work on USB-out from a WiiM Ultra?

Once set to an input and a volume, then powered off (physically), does it return to these settings when power comes back?

I would like to use it to get XLR output and voltage behind a WiiM Ultra, but these units would then be stowed away in a cabinet.
 
A couple of questions, maybe owners of this DAC have some info for me.

Does this DAC work on USB-out from a WiiM Ultra?

Once set to an input and a volume, then powered off (physically), does it return to these settings when power comes back?

I would like to use it to get XLR output and voltage behind a WiiM Ultra, but these units would then be stowed away in a cabinet.

"It's a nice feature that the D-6s memorizes all settings when the power is cycled; i.e. when it got switched of and on again, signal source, volume setting, etc. are in the same state like before. The unit even memorizes the power state. When you cycled power with the D-6s "on", it will be "on" when you reconnect power."

 
Got this little box via amazon from ShenzenAudio. Good price btw if anyone is looking (EU).

Any way to tell the flashed firmware version?

And is it known if the mislabeled filters have been fixed in the latest firmware (1.2) or did they not touch the manual/factual list mismatch?
 
have been fixed in the latest firmware (1.2)

The latest I see here is v1.1.

 
The latest I see here is v1.1.

When I unpack it I see:

SMSL D-6S_MCU v1.2_241008.exe

From the english page -> download

Not that the exact version number is important.
 
When I unpack it I see:

Ah. Good catch. Looks like this one was built in October of 2024. If you bought your DAC more recently than that, you may already be running it.

$ unzip -vl SMSLD6SMCUFWV101.zip
Archive: SMSLD6SMCUFWV101.zip
Length Method Size Cmpr Date Time CRC-32 Name
-------- ------ ------- ---- ---------- ----- -------- ----
197647 Defl:N 160519 19% 2023-01-03 11:48 ca7ce543 SMSL D-6S_MCU v1.2_241008/SMSL D-6 SMCU Update Instructions(EN).pdf
307200 Defl:N 151368 51% [B]2024-10-08[/B] 11:25 107aab1d SMSL D-6S_MCU v1.2_241008/SMSL D-6S_MCU v1.2_241008.exe
0 Stored 0 0% 2024-10-08 14:55 00000000 SMSL D-6S_MCU v1.2_241008/
-------- ------- --- -------
504847 311887 38% 3 files
 
I read that the list of filters was corrected for other model(s) using the ESS9039Q2M via firmware updates.

Would like to find out what's what here.
 
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