SMSL DO400 Fully Balanced Audio Decoder & Headphone Amplifier

[nanook]

The FW update sequence that finally worked for me:

- DO400 is plugged in (mains and USB), but power switch at rear of unit is "off"
- install SMSL driver (not sure if it is really needed for FW-update)
- unpack "DO400MCUVA3.rar" (contains zipped loader directory "ISP_PC_EN2" and hex file "IAP_DO400_1V0A3.hex")
- unpack "ISP_PC_EN2.zip" to the desktop and make sure there is only one level of folder "ISP_PC_EN2"
(I moved all files one level up such that the loader "ispV2.4.exe" and all other files reside in "C:\Users\xxxxx\Desktop\DO400\ISP_PC_EN2\")
(the executable e.g. is now located here: "C:\Users\xxxxx\Desktop\DO400\ISP_PC_EN2\ispV2.4.exe")
(I copied the hex file to this location: "C:\Users\xxxxx\Desktop\DO400\IAP_DO400_1V0A3.hex" to have it near to the rest of the stuff)
- start the executable "ispV2.4.exe" (the GUI should come up)
- make sure Device is "MM32F103xx_o" (upper right corner of the GUI)
- open pull-down menu "File -> open" and search for the hex file "IAP_DO400_1V0A3.hex"
- select hex file "IAP_DO400_1V0A3.hex"file and click "open" (after a few seconds the GUI freezes for ca. 30s)
- make sure only boxes "Run_Prog" and "vefify" are checked (I did separate runs for "Run_Prog" and "Verify", i.e. only one box checked at a time)
- press volume knob and hold it pressed
- cycle rear power switch and hold volume knob pressed for at least 5s
(display of unit should stay dark)
- GUI still shows "Disconnect" in red
- open pull-down menu "Options -> Connect"
- GUI should should show "Connected" in blue now
- click large button "Start_Program"
(A green bar should signal progress; it takes about 80s to program and 80s for verification)
- open pull-down menu "Options -> Disconnect"
(GUI should now display "Disconnect" in red again
- switch off DO400
- close loader GUI by clicking the "x" in the upper right corner

Please find attached the screenshots of the GUI after the "Run_Prog" and after the "Verify" run. Doing this in two separate runs assures you that the firmware was really updated.

In case something is not clearly described here, please let me know and I will update / correct these instructions.

 

[arrow0309]

The FW update sequence that finally worked for me:

- DO400 is plugged in (mains and USB), but power switch at rear of unit is "off"
- install SMSL driver (not sure if it is really needed for FW-update)
- unpack "DO400MCUVA3.rar" (contains zipped loader directory "ISP_PC_EN2" and hex file "IAP_DO400_1V0A3.hex")
- unpack "ISP_PC_EN2.zip" to the desktop and make sure there is only one level of folder "ISP_PC_EN2"
(I moved all files one level up such that the loader "ispV2.4.exe" and all other files reside in "C:\Users\xxxxx\Desktop\DO400\ISP_PC_EN2\")
(the executable e.g. is now located here: "C:\Users\xxxxx\Desktop\DO400\ISP_PC_EN2\ispV2.4.exe")
(I copied the hex file to this location: "C:\Users\xxxxx\Desktop\DO400\IAP_DO400_1V0A3.hex" to have it near to the rest of the stuff)
- start the executable "ispV2.4.exe" (the GUI should come up)
- make sure Device is "MM32F103xx_o" (upper right corner of the GUI)
- open pull-down menu "File -> open" and search for the hex file "IAP_DO400_1V0A3.hex"
- select hex file "IAP_DO400_1V0A3.hex"file and click "open" (after a few seconds the GUI freezes for ca. 30s)
- make sure only boxes "Run_Prog" and "vefify" are checked (I did separate runs for "Run_Prog" and "Verify", i.e. only one box checked at a time)
- press volume knob and hold it pressed
- cycle rear power switch and hold volume knob pressed for at least 5s
(display of unit should stay dark)
- GUI still shows "Disconnect" in red
- open pull-down menu "Options -> Connect"
- GUI should should show "Connected" in blue now
- click large button "Start_Program"
(A green bar should signal progress; it takes about 80s to program and 80s for verification)
- open pull-down menu "Options -> Disconnect"
(GUI should now display "Disconnect" in red again
- switch off DO400
- close loader GUI by clicking the "x" in the upper right corner

Please find attached the screenshots of the GUI after the "Run_Prog" and after the "Verify" run. Doing this in two separate runs assures you that the firmware was really updated.

In case something is not clearly described here, please let me know and I will update / correct these instructions.

Done it this way and it's dead now, no turning back on again

 

[arrow0309]

Done it this way and it's dead now, no turning back on again

I tried it again, this time was similar to the first one, way quicker than 80s, both of times (maybe it's had the update already?) and it's still dead.
Here's the screenshot:
Not turning back on.

 

[arrow0309]

The reason for the firmware update was no sound / no device after powering it back on from the volume knob every time at the new windows load, had to turn it off / on from the rear power knob (the standby mode with a red line was always present in standby overnight) so I don't know, maybe a broken unit?
Was bought from amazon.co.uk wearhouse as "used like new", the box was "used" but the device pristine, still with the film on the display.

Waiting for feedback, in case I will return it. The price was good, £350, I think I'm just unlucky.

BTW,
I've just left a message to SMSL support as well, I don't feel confident about a solution though.

 

[nanook]

I'm sorry to hear you are having problems. I actually double checked the sequence I posted with a verify run this afternoon.

Are you sure you did load the correct hex file?
The codesize and checksum etc. look very different.

Seems also that in your configuration the baudrate is different compared to my configuration.

 

[arrow0309]

I'm sorry to hear you are having problems. I actually double checked the sequence I posted with a verify run this afternoon.

Are you sure you did load the correct hex file?
The codesize and checksum etc. look very different.

Seems also that in your configuration the baudrate is different compared to my configuration.

Yeah, the hex file is unique you can't miss it.
Some of the data looks different yeah, also the time required, it did all very fast.
The archive was downloaded from their site days ago. Not available anymore as I noticed.
In case can you provide a different link for the firmware?
I should try to rewrite it again supposing mine was somehow corrupted.
In the meantime waiting for their customer service to reply back.

 

[nanook]

Yeah, the hex file is unique you can't miss it.
Some of the data looks different yeah, also the time required, it did all very fast.
The archive was downloaded from their site days ago. Not available anymore as I noticed.
In case can you provide a different link for the firmware?
I should try to rewrite it again supposing mine was somehow corrupted.
In the meantime waiting for their customer service to reply back.

Your screenshot looks like you can write and verify properly.
I can pack the folder that I have been using successfully and post it here.
You'll have the configuration then as well.

I'm busy right now, but will do it in a few hours. Ok?

 

[arrow0309]

Your screenshot looks like you can write and verify properly.
I can pack the folder that I have been using successfully and post it here.
You'll have the configuration then as well.

I'm busy right now, but will do it in a few hours. Ok?

Hi mate, just flashed the older V2 firmware found here on this thread.
It came back to life
The process took it's time (as it should) unlike my previous attempts with the "corrupted" (I suppose) V3.
For now I'm good, let's wait to see if a V4's incoming (in case). Also because I'm leaving for a couple of weeks (and I'll only bring the smaller Xduoo Bal2 with me)
Here's the picture of the firmware result:

 

[nanook]

Good to hear you got it up again, congratulations!
In case no V4 shows up and you want to try V3 at some point of time I have attached a zip of the folder that worked for me.
The archive is checked with Windows Defender and I'm quite cautious in general, but of course I cannot guarantee it's virus free.

 

[nanook]

Yeah, the hex file is unique you can't miss it.

Actually there are two xxxx.hex files. One in the folder where the loader executable is located (this one is the wrong one) and one that was packed in the RAR file (IAP_DO400_1V0A3.hex).

Anyway I am wondering why SMSL took this firmware update from their website.

 

[RedEyeNinja]

Actually there are two xxxx.hex files. One in the folder where the loader executable is located (this one is the wrong one) and one that was packed in the RAR file (IAP_DO400_1V0A3.hex).

Anyway I am wondering why SMSL took this firmware update from their website.

Seems like there are new products coming... Such as the H400. Maybe the web guy made a mistake when updating their site?

 

[Roland68]

Actually there are two xxxx.hex files. One in the folder where the loader executable is located (this one is the wrong one) and one that was packed in the RAR file (IAP_DO400_1V0A3.hex).

Anyway I am wondering why SMSL took this firmware update from their website.

There seem to be two more missing.

 

[nanook]

Indeed.... really strange.
Let's hope, SMSL offers new firmware updates and does not miss the opportunity to correct the PCM filter names in the menu of the DO400.

 

[arrow0309]

Actually there are two xxxx.hex files. One in the folder where the loader executable is located (this one is the wrong one) and one that was packed in the RAR file (IAP_DO400_1V0A3.hex).

Anyway I am wondering why SMSL took this firmware update from their website.

I know and obviously I used the external, IAP one (as per readme pdf file as well).
One other thing I did differently with my successful V2 firmware update was plugging the USB cable (Audioquest Forest) on (one of my) desktop pc usb 2.0 port on the rear i/0 of my motherboard (Z790 Nova) instead of using it through a powered usb 3.0 hub (as it was before) but I doubt could have this been an issue.

 

[arrow0309]

There seem to be two more missing.
View attachment 374200

I still don't see these files, are you on the Chinese different site?

 

[nanook]

Roland68 obviously had an older screenshot.
There are two more entries missing on both, the Chinese and the English website now compared to his screenshot.

 

[RedEyeNinja]

I can also attest both the English and Chinese sites are no longer hosting any firmwares for dacs and amps.

 

[MicrosPL]

Zaktualizowano slajdy dotyczące opcji filtra PCM.
Z moich pomiarów wynika, że opis filtrów PCM w menu DO400 jest błędny w przypadku kilku ustawień filtrów.
Ponieważ ludzie eksperymentują z tymi opcjami filtrów i poświęcają czas i wysiłek, aby usłyszeć różnice, informacje powinny być wiarygodne.

--> Czy ktoś może potwierdzić pomiar w dziedzinie czasu (impuls Diraca)?

Jeśli moje pomiary się potwierdzą, poproszę SMSL o wydanie poprawionego oprogramowania sprzętowego.

Have you emailed your measurements and observations to SMSL? Your conclusions are very interesting and it would be great if they were included in the firmware update.

 

[nanook]

I have not yet emailed SMSL yet, since I was hoping someone could confirm my observations.
But of course, SMSL can check this easily, so maybe SMSL is following this thread.

@SMSL-Mandy: Can you please initiate that the design crew double-checks that the PCM filter name in the display matches the actual filter response (impulse response and frequency response)?
In case they are mixed up indeed, please provide us with a corrected firmware.

For details see: https://www.audiosciencereview.com/...ecoder-headphone-amplifier.47766/post-1981982

For the D-6s, the PCM filter description given in the manual does not match reality as well according to my measurements - since just a number is displayed, an update of the manual would do.

 

[MicrosPL]

Nie wysłałem jeszcze e-maila do SMSL, ponieważ miałem nadzieję, że ktoś potwierdzi moje obserwacje.
Ale oczywiście SMSL może to łatwo sprawdzić, więc może SMSL śledzi ten wątek.

@SMSL-Mandy: Czy możesz zainicjować, aby zespół projektowy dokładnie sprawdził, czy nazwa filtra PCM na wyświetlaczu odpowiada rzeczywistej odpowiedzi filtra (odpowiedź impulsowa i charakterystyka częstotliwościowa)?
Szczegółowe informacje można znaleźć na stronie: https://www.audiosciencereview.com/forum/index.php?threads/smsl-do400-full-balanced-audio-decoder-headphone-amplifier.47766/post-1981982

Maybe you're right, but on the other hand, you don't lose anything by writing an e-mail to SMSL. They will certainly verify it in their own way or they won't respond if they don't have time.