Roon settings for DSD files via SPDIF

slai · October 15, 2021, 2:30am

Hi everyone,

I have a rather novice question regarding the Roon settings for DSD files playing via SPDIF. I understand that SPDIF does not decode DSD files. I have a DDC connected to the DAC via SPDIF and I have some DSD files I would love to listen to.

I have set the DSD playback strategy as “convert to PCM”, Max sample rate (PCM) at max “up to 768kHz”, under DSP, Sample rate conversion is “enabled”. With this settings, there are no sound during DSD files playback but it functions well with normal WAV/FLAC/ALAC files.

Or have I misunderstood incorrectly? Any advice is greatly appreciated

David_Snyder · October 15, 2021, 2:44am

Sorry to hear that you are encountering issues with DSD playback. I’m just another Roon subscriber, but I thought I’d ask a few questions, if you don’t mind.

What is a “DDC”?

Specifically which DAC are you using?

Please share a screenshot of your signal path in Roon. For example:

I imagine it’s something simple.

slai · October 15, 2021, 2:51am

@David_Snyder hi David, I am also a regular Roon user, very much like you.

DDC = digital to digital converter, perhaps it is also known as USB Audio Bridge. am using the Singxer SU-6

The DAC in use in this set up is an old LKS MH-DA002.

David_Snyder · October 15, 2021, 2:58am

That signal path looks like it’s USB out of your MAC and directly into the DAC. No Allo USBridge and no S/PDIF.

Have you tried switching the active input on the DAC to USB? This is a reach since what I’m seeing does not match what you described.

Edit: scratch most of that, I see you are not using the Allo. Sorry, long day

David_Snyder · October 15, 2021, 3:02am

So, USB out of your Mac into the SU-6 and then S/PDIF into the DAC. You need to set the sampling rate limits in Roon to 24-bits, 192 kHz

slai · October 15, 2021, 3:21am

Below is my signal path:

MacBook Pro → USB C-USB B cable → Singxer SU-6 → Coaxial SPDIF → LKS MH-DA002 DAC → Amplifier → Headphone

slai · October 15, 2021, 3:22am

thanks David. Upon adjusting to 24bit 192kHz, I get statics sounds in my headphones. But if I set as 16bits 96kHz, the static sounds disappears

David_Snyder · October 15, 2021, 3:52am

Interesting. Could be that the highest rate that your DAC supports over S/PDIF is 96 kHz. Make sure that you are using a 75Ω digital cable and not a standard RCA cable. May be obvious, but I’ve seen some wild things out there.

slai · October 15, 2021, 5:16am

indeed the SPDIF cable is a 75Ω cable…as this DAC is rather old I am unable to find the specifications to verify on the SPDIF limitations.

Henry_McLeod · October 15, 2021, 6:05am

That DAC is circa 2013 and is a bit of a beast, more than capable of playback of DSD up to DSD128. The problem is the DDC will allow you to set up any bit rate it is capable of regardless of what you have it connected to. In order to test it properly plug USB direct into your core and Roon should pick up its capabilities automatically. If you use the DDC then begin with maximum 192/24 and try DSD settings as DOP DSD64. That might work. Otherwise ditch the DDC for decent USB isolation and go that route.

slai · October 15, 2021, 6:29am

The MH-DA002 can play DSD256 when connected to MacBook Pro and when the Singxer SU-6 DDC is connected to the Holo Audio MAY KTE, it can also play DSD256

Below contains some information extracted from Kitsune SU-6 webpage

Henry_McLeod · October 15, 2021, 6:49am

I owned an SU 6, so I know it’s capabilities are tied to the DAC and specifically the input you choose. The Kitsune is using its i2S input, fully capable of mirroring USB performance. You are using coaxial SPDIF normally only specified up to 192/24 and maybe DOP at a push.

slai · October 15, 2021, 6:57am

The funny thing is that 192/24, 192/16, 96/24 are problematic via SPDIF on the SU-6 pairing with the DA002.

Henry_McLeod · October 15, 2021, 7:58am

That is strange. You can try a different cable but otherwise it is difficult to say what the problem might be. I used my SU 6 with an AudioByte Black Dragon via the i2S so never used it into other inputs. I’m trying to remember what you could adjust using the dip switches but it may have just been the way the DDC handles DSD. I wish I could be of more help.

slai · October 15, 2021, 8:59am

your inputs are greatly appreciated. Since both SU-6 & MH-DA002 are working well independently playing DSD files in other contexts mentioned earlier, it can be assumed that the possible weak link is the coaxial SPDIF cable. Will only know better after getting a new cable to test it out.

Martijn_Bos · February 13, 2022, 5:33am

I ran into SPDIF issues with DSD as well today. I switched over to USB and the issue is resolved. After reading some more I realized SPDIF indeed isn’t a good connection type for DSD.

How did you resolve it? Did you go for I2S?