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SMSL D300 Review (Balanced DAC)

Something else I wanted to mention here:

If you look at the datasheet there is a direct DSD mode If the DAC is in fixed volume mode.

It's the same thing that the AKM chips do in DSDD or DSD bypass.

The DSD input goes directly to the output stage and there is no messing around with the signal.

That's really cool for people that use HQPlayer and use the filters there.

But AKM chips need to be set to DSD direct mode and the manufacturer of the DAC needs to support that feature like the SMSL D400 ex or the gustard A26.
The ROHM-chip in the D300 is always in that mode when using DSD.

The programmer of HQPlayer measured the D300 with DSD as well and suggests the cut-off frequency of 13khz with DSD512. That gives you 104khz.
And with DSD256 the cutoff frequency should set to 26khz.
 
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The programmer of HQPlayer measured the D300 with DSD as well and suggests the cut-off frequency of 13khz with DSD512. That gives you 104khz.
And with DSD256 the cutoff frequency should set to 26khz.
So based on the DSD quality, i have to set cut-off frequency manually on the D300? What is it for, why do we need to do that?
I've been curious that feature on the D300 but don't know how to look up, can you please explain more or share some key words or articles about it?
Thanks
 
So based on the DSD quality, i have to set cut-off frequency manually on the D300? What is it for, why do we need to do that?
I've been curious that feature on the D300 but don't know how to look up, can you please explain more or share some key words or articles about it?
Thanks

Best thing would be go to the roon forum and search for HQPlayer.

You need to upsample to DSD256 or DSD512 to get the best out of the DAC. And set the. Cutoff frequency accordingly to the samplerate that you use.
 
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Mine is different but has a clicking sound using Audiolab streamer as a transport when playing HD 48khz + from AMHD but works fine with other sources. I now use WiiM as a transport without issues. Likely different issues but wanted to share. cheers
my very new d300 has no problem with coax and even bt input but when used with a MacBook connected with a usb cable stop playback after few seconds? any help?.Very likable anyway, reminds the burr brown cpm 63 chip
 
This is our first dac on Rohm Chip. D300 sounds more like playing vinyl, the felling more analog
Does this imply that more DACs with the Rohm chip are coming?
 
Because they have a sale ?

It would certainly be nice, ROHM Chips have a direct DSD mode like AKM chips.
Not really, but any reason would be fine.

Actually, I was referring to SMSL-Mandy stating, "This is our first dac on Rohm Chip. D300 sounds more like playing vinyl, the felling more analog".
First. Dac. On. Rohm. Chip.
 
I went through this whole thread due to the fact I had serious interest in this dac. And also recently purchased the A300 to pair with it. Currently using the D-6.
Now…I’m on the fence about the D300 with all the reported issues. Is there anyone here who has had trouble free units from day one to present? Cheers
 
I went through this whole thread due to the fact I had serious interest in this dac. And also recently purchased the A300 to pair with it. Currently using the D-6.
Now…I’m on the fence about the D300 with all the reported issues. Is there anyone here who has had trouble free units from day one to present? Cheers


Here. Connected to a headphone amp (XLR). And only input i use is USB from a raspberry pi.
 
Here. Connected to a headphone amp (XLR). And only input i use is USB from a raspberry pi.
Thanks for the reply. I also plan to use USB(from PC/Tidal and Foobar)but also OPT from TV. Most likely RCA to A300. The A300 will be running the Elac UBR 62’s.

All the qualities I’m hearing bout the Rohm chip and the fact that I actually live in Kyoto(where it’s made) have me interested. I also play concerts at the Rohm Theater and am a fan of their work towards providing scholarships to young artists.
 
Thanks for the reply. I also plan to use USB(from PC/Tidal and Foobar)but also OPT from TV. Most likely RCA to A300. The A300 will be running the Elac UBR 62’s.

All the qualities I’m hearing bout the Rohm chip and the fact that I actually live in Kyoto(where it’s made) have me interested. I also play concerts at the Rohm Theater and am a fan of their work towards providing scholarships to young artists.

Just give it a chance in that case. As far as I know it's the only rohm DAC at the moment expect daps with dual Rohm Chips (interesting also).

I think most problems mentioned are either because of how Mac's handle the sleep mode of the XMOS chip (there are workarounds for that) and issues with DSD..
(I have none with my Raspberry pi).
 
Received a SMSL D300 unit today. I was curious if my old ears would hear the difference between the output of the DAC of my Node 2i and this unit. Yes there is a noticeable improvement. Bigger stage, more detail, more open, more depth, better placement of instruments and most important (for my ears) a nicer sound. COAX output of the node 2I into the D300.

Happy man here. I'm sure there are better systems to buy, but for now I'm satisfied, very satisfied. Perhaps one day I will be curious and start a search for a replacement of my tube amp o_O, but for now I'm done searching. I will be listening.
 
This morning I thought my COAX input was gone bad too. After an update of my Node 2i, I just could not hear any music anymore over the Node 2i and the D300. Playing vinyl was fine. Something wrong in the streaming chain. Maybe COAX input died too, like others reported here.

Than my eye saw OPT on the display, in stead of COAX. :rolleyes:. I am sure I did not change to optical input, why would I, I have a COAX interconnect with the Node 2i. So changed in the menu back to COAX and of course it plays wonderful again.

Strange, but now I know it can happen and I know what to do, no worries for me. I enjoyed music the whole morning, until the wife came back home that was :facepalm:.
 
It would certainly be nice, ROHM Chips have a direct DSD mode like AKM chips.
Actually this ROHM chip only operates in DSD Direct mode - there is no other mode, unlike AKM

You can see from block diamgram, DSD always bypasses DSP. No upsampling, no modulator, no digital volume control


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I tried to rewrite the D300 MCU firmware update work in an easy-to-understand manner.


Prepare for update

Unzip the downloaded update file "SMSL D300_MCU_FW 221012".

”IAP_D300_MM32_1v1.hex” in the unzipped folder ”SMSL D300_MCU_FW 221012” is the configuration file to be specified in the update work.

Furthermore, unzip "ISP_PC_EN.zip" in the folder.
"ispV2.4.exe" in the unzipped folder is the update tool.

Start update

Turn off the power switch on the back of the D300 before starting the update process.
Remove the USB cable connecting the D300 and the PC.

Click "ispV2.4.exe" to launch the update tool.

Click "File" in the upper left corner of the screen, then click "Open".

On the screen to specify the installation file, specify "IAP_D300_MM32_1v1.hex" in the unzipped folder and click "Open" at the bottom right.
Wait 30 seconds for the update tool to prepare the files for deployment. At this time, there is no change on the PC screen.

After 30 seconds, connect D300 and PC with USB cable.
Hold down the FN button and turn on the power switch on the back of the D300. Release the FN button after 5 seconds.
At this time, the screen of D300 remains off and there is no change.
"Disconnect" is displayed at the bottom left of the PC screen.

If the D300 normal screen is displayed by this operation, redo the operation.

After 30 seconds have passed, click the "handshake icon" in the upper right corner of the PC screen.
Then "Disconnect" at the bottom left of the screen will change to "Connect".

Click “Start Program” displayed near the center left of the screen.

The firmware update process will begin and you will see flowing text on the right side of the screen indicating the processing steps.

When the update is finished, "Complete" is displayed and the screen of D300 lights up and it becomes normal operation.

This completes the update work.


Has anybody here been able to successful do the February 2023 firmware update? Both MCU and USB updates?

No brickings of the device?

Can anyone share recommended instructions for how to update ?


@Snoopy @Happyhammer @Toku @SMSL-Mandy

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I realize this unit has been out for a minute now and well discussed. I had been seriously considering(and still might in the near future) picking up an R2R Dac. Specifically the Gustard R26 or Denafrips Pontus 2 12th. The D300 had been on my radar for a while prior and I decided to go ahead and pick one up and end up eventually using it in my upstairs room. Well, it’s currently in my living room setup paired with my Belles Soloist stack and EVO’s and it is pretty much exactly the sound I was after. Wow. Spending time listening to all genres and I can’t yet point out a weakness to my ears. It certainly has that semi-warmer, analogue-ish sound spectrum. It’s almost the perfect match for my current setup. The Wharfedale’s really come alive with the d300 in the chain. I previously had a D-6 with the dual AKM 4493 chips. While the D-6 does a great job, the d300 has me listening for longer sessions and not wanting to leave. I’m going to enjoy this one here for a while before “stepping up.”

I actually live in Kyoto, Japan where the Rohm chip is made. I also play concerts(orchestra) regularly at the Rohm Theater. They are a fantastic company which supports young artists with scholarship money and such.

Anyhow, I’d love to hear from those whom have had this DAC up against an R2R type.

Cheers
 
Has anybody here been able to successful do the February 2023 firmware update? Both MCU and USB updates?

No brickings of the device?

Can anyone share recommended instructions for how to update ?
Installing the SMSL D300 FW 221012 turns your DAC into a "speaker killer".
You can read more details here
 
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