I have a problem I think in that I cannot get Roon to play DSD 256.
I am playing from a Mac mini with Roon server to a Roon endpoint on SOTM SMS 200 and then to a Mytek Brooklyn.
Native DSD 128 works Ok but DSD 256 downsamples to PCM.
Device setup within Roon only has options for max sample rate of DSD 128 which I have turned off anyway.
The SMS 200 is correctly set for max DSD of DSD256.
Strange thing is I can play native DSD 256 from Roon to a HQPlayer endpoint OK.
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Is this because Roon does not support DSD 256 over DOP, 128 being the highest?
Roon supports DSD256 over DoP, but the DAC must be able to accept the 768kHz PCM stream that’s used as an envelope for DSD256 in DoP–very few DACs can do this, but we support the ones that do.
The majority of DSD DACs (not sure if Mytek Brookylen is one of them) can only do DSD256 in native mode.
Maybe you can configure the sMs-200 in Native mode? This is something SoTM might need to help you with.
Thanks for your clear answer. The sms200 does have an option for DSD 256 native which I have tried but still get same results. I will see what SoTM says.
Thanks.
OK I have been in touch with SoTM and they have not offered any solution that works. So in order to simplify the problem can you answer this please.
Mac Mini running Roon Server connected via ethernet to SMS200 Roon Ready.
DAC will definitely accept DSD Native. Assuming all settings are correct.
Should I have a menu option in Device settings that says DSD Playback Strategy with an option of DSD Native as in your Knowledge Base?
Thanks.
No–that dropdown is for software-based endpoints connected directly to Roon, Roon Bridge, or Roon Server.
On a hardware bridge like the sMS-200, it’s up to the hardware to manage the details of how it communicates to downstream USB devices.
Here comes the ugly technical part…
Native DSD on hardware devices like this requires a lot of support–usually a per-DAC effort–from bridge vendors. This is because they’re based around Linux, and there is no unified way that devices handle Native DSD on Linux, so the operating system on the device needs to be patched to add support for devices one at a time.
I don’t know anything about what SoTM promises in this area, nor do I have a sense of how complete their device-level support for Native DSD DACs is. Since it’s a thing that they would need to keep up with one device at a time, on an ongoing basis, it takes a lot of commitment to be continually up-to-date in this area.
The first step is to be confident that your DAC supports Native DSD not just in general, but on Linux, since those aren’t always the same thing. I think that’s the case–at least the project that is working on this stuff looks like they added experimental support for the Brooklyn about a year ago. That leaves two questions:
- Did the “experimental” support work out?
- Does the SotM firmware include the patch from that project that adds the support?
I suspect that the answer to #1 is “yes” since I don’t see signs that they pulled the patch back and I think I’ve heard of people using that DAC successfully in Native mode on Linux. I’m afraid SoTM is the only one who can answer the second question.
I know this is a more complicated answer than you were hoping for. Maybe the extra information will help you push them in the right direction?
Thanks for your answer but one more point please and then I will get back to SoTM.
With DSD 256 I get this:
If I understand correctly it is because I cannot sent DSD 256 over DOP so it is converted to PCM.
But with DSD 128 I get this:
which seems be sending DSD directly, so is this Native? If it is then I am confused as to why 128 is working and not 256.
Thanks for your help.
Hm, so that means native is working, but the sMS-200 either isn’t reflecting DSD256 capabilities back to Roon, or there’s a Max DSD rate configured on the Roon side.
I just plugged in a DAC that I know does DSD256 in native mode on all recent Linux kernels into the SoTM and DSD256 worked for me:
So we know it’s possible with only the DAC different between what I have here and what you have there–the only variable I can’t check is the DAC.
If your screens look like mine, this is probably an issue with the sMS-200 either reading the wrong capabilities from the DAC, or mis-reporting them to Roon. It’s an annoying situation.
I wish I had a Brooklyn in front of me…could probably fiddle with it and get the exact answer out as to what’s going on. We’ll ping Mytek about getting one of those for our collection.
Thats excellent information. Yes my screens look exactly as yours. I’ll get back to SoTM now. If I get any info I’ll pass it back here.
Thanks again.
Good news this problem is now solved and DSD 256 is working correctly!
I have been on a TeamViewer session with SoTM. They found that a file was missing from the last few updates and the DSD rate and mode were not being set correctly, This should be corrected in the next update, V3.4.
I must say the customer service from SoTM was excellent.
Thanks for the help from the Roon people as well.
Ian
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I’m streaming from NUC Win10 Roon server to sotm sms-200, which is connected to mutec mc3+ USB.
Previously I config sotm DSD mode as DoP, and I find Roon saw its max DSD sample rate as “up to DSD128”.
sotm has just release new firmware which add “native DSD” support to my mutec.
So after the upgrade, I change the sotm DSD mode to “native”
Then in Roon, I find the max DSD sample rate is now “up to DSD256”
I can playback DSD256 through sotm sms-200 to mutec now 
