DSD transcoded on the fly to PCM-192kHz?

[daydreamer]

I've been enjoying the new Squeezelite functionality of the WiiM Pro and thought I'd see what would happen if I played some of my .dsf files from my LMS music library. To my surprise, music immediately played in decent sound quality with my DAC indicating PCM 192kHz.

Firstly, I was not expecting this to work at all, so good news! Second, I verified that no dsdplay executable was running on my LMS server, indicating that the conversion was being done inside the WiiM Pro. Finally, I note that conversion from 2.8224 MHz to 192kHz involves asynchronous rate conversion, while the more logical and simple conversion would have been to 176.4kHz, and could probably have been done with higher technical quality.

If this DSD conversion feature is official, I welcome it, but would have preferred pass through of DoP, or if conversion to PCM is done then a higher quality resampling to 176.4kHz would be desirable. (To my ears, WiiM's conversion from 2.8224MHz 1-bit to 192kHz is not of the same quality as Roon's server-side conversion of the same source material to 176.4kHz when sent via my WiiM Pro to the same DAC.)

Can anyone confirm the current status of DSD processing on WiiM Pro and Pro+ products?

Charles.

 

[Brantome]

Tried it again with this file from the Oppo site and it's breaking up with my Pro playing from LMS, but is fine on my Pro Plus, as it is playing natively on my Linn. So maybe it's file dependent and the squeezelite client isn't the solution I thought it might be...

http://download.oppodigital.com/hra/davidelias/01%20-%20David%20Elias%20-%20The%20Window%20-%20Vision%20of%20Her%20%28DSD64%29.dsf

 

[onlyoneme]

I've just made some tests with the Pro Plus and this file

http://download.oppodigital.com/hra/davidelias/07%20-%20David%20Elias%20-%20Acoustic%20Trio%20-%20Rodeo%20On%20A%20Ridge%20%28DSD64%29.dsf

and I got it sent in DSD format from WiiM to ADI-2.

First case - Foobar2000 and the Pro Plus as UPnP target with foo_out_upnp - passed
Second case - Foobar2000, SMSL PO100 Pro as USB-SPDIF converter connected to toslink input of the Pro Plus - also passed

 

[onlyoneme]

Second case surprised me a lot

 

[onlyoneme]

My Pro also passed first case.

 

[Brantome]

My Pro also passed first case.

I’ll need to have another try with my Pro then - I used the WiiM Home app accessing my Minimserver service and it was breaking up quite badly. I’ll try BubbleUPNP and check my Minimserver settings

 

[onlyoneme]

Although Squeezelite client on the Pro / Pro Plus is capable of decoding DSF file to PCM, the quality here is degraded to 16 bits.

 

[Wiimer]

Please tell me ignorant.
Have you come to a conclusion about this?
In other words, as stated in the specifications, does the WiiM Pro Plus support DSD?
Yes or No ?

Thank you.

 

[onlyoneme]

Not easy to give a definitive answer. It looks to me that:
- squeezelite client on the WiiM can decode DSF files to PCM with limited quality - no DSD on the DAC
- WiiM can't do that itself over UPnP
- WiiM can work with DSD stream if it's incoming in DoP form, ie. packed into FLAC or WAV but with maintained DSD data - this way the DAC can retrieve and process DSD stream

 

[onlyoneme]

All above is about the external DAC, but it's at least partially valid for an internal DAC of the Pro Plus - for example it cannot decode DSF over UPnP regardless of the selected output.

 

[Brantome]

My Pro and Pro Plus are now not playing that same track from LMS without breaking up and I’m not aware I’ve changed anything since yesterday. I’m confused…

 

[onlyoneme]

It works to me actually:



Stream converted on the WiiM to PCM 192/16 before sending to the DAC.

 

[Wiimer]

Not easy to give a definitive answer. It looks to me that:
- squeezelite client on the WiiM can decode DSF files to PCM with limited quality - no DSD on the DAC
- WiiM can't do that itself over UPnP
- WiiM can work with DSD stream if it's incoming in DoP form, ie. packed into FLAC or WAV but with maintained DSD data - this way the DAC can retrieve and process DSD stream

I don't think I'll be listening to DSD in the future because I'm only streaming, but I just want to deepen my knowledge of WiiM.

Thank you for teaching me politely!

 

[daydreamer]

Although Squeezelite client on the Pro / Pro Plus is capable of decoding DSF file to PCM, the quality here is degraded to 16 bits.

Great observation. I noticed the sound with WiiM transcoding DSD64 to 192kHz/16 is not as enjoyable as the same file played via Roon (which reports the signal chain as DSD64->3528kHz PCM -> 174.6kHz (float) -> 172.6kHz 32-bit -> RAAT -> WiiM Pro->DAC).

I know very few of us have DSD libraries, but for those of us that do, the option to pass DoP unaltered to an attached DAC would be awesome!

Charles.

 

[madbrain]

I got a new Wiim Pro Plus and am trying to play some DSD64 files from JRiver Media Center 31 (DSF, SACD ISOs). I don't have an external DAC. I use the RCA analog output of the Wiim, along with the Multi-channel input on an old receiver to avoid AD/DA pass.

Is there any way to pass DSD64 directly from JRiver MC to the Wiim, without configuring MC for PCM conversion (which I haven't figured out quite yet) ?

 

[daydreamer]

I got a new Wiim Pro Plus and am trying to play some DSD64 files from JRiver Media Center 31 (DSF, SACD ISOs). I don't have an external DAC. I use the RCA analog output of the Wiim, along with the Multi-channel input on an old receiver to avoid AD/DA pass.

Is there any way to pass DSD64 directly from JRiver MC to the Wiim, without configuring MC for PCM conversion (which I haven't figured out quite yet) ?

The answer appears to be "no" for your use case. It seems WiiM can (unwittingly) pass DoP to an external DAC that supports DSD over PCM, and also can convert DSD to a compromised PCM when emulating a Logitech Squeezebox. Neither of these meets your requirement. Things may or may not be changing depending on whether the developers decide to add explicit support for DSD, or remove such accidental support as exists.

Charles.

 

[madbrain]

The answer appears to be "no" for your use case. It seems WiiM can (unwittingly) pass DoP to an external DAC that supports DSD over PCM, and also can convert DSD to a compromised PCM when emulating a Logitech Squeezebox. Neither of these meets your requirement. Things may or may not be changing depending on whether the developers decide to add explicit support for DSD, or remove such accidental support as exists.

Charles.

Charles,

Thanks for your reply. That's very unfortunate. I have a number of DSD albums.
I set JRiver to transcode DSD to 192 kHz PCM. I experienced some problems, though. Multiple times, in the middle of playing an album where transcode had started successfully, when changing tracks, I got white noise out of the WiiM. It really scared not just me but my cat when my receiver was set to +9dB. The first time it occurred, I was able to stop and play again. The second time, I had to reboot the WiiM Pro Plus to get any more sound out of it.

Has anyone else experienced this white noise problem ? It is a random inconsistent problem. Not sure why transcode would be any different than playing straight 192 kHz PCM files from JRiver. I don't have any of those, though. Maybe I need to do a file transcode of my SACD ISOs to PCM and try playing them to see if the problem happens again. I have never heard the white noise when transcoding within JRiver without streaming to Wiim - ie. using a local renderer.

 

[madbrain]

Has anyone else experienced this white noise problem ? It is a random inconsistent problem. Not sure why transcode would be any different than playing straight 192 kHz PCM files from JRiver. I don't have any of those, though. Maybe I need to do a file transcode of my SACD ISOs to PCM and try playing them to see if the problem happens again. I have never heard the white noise when transcoding within JRiver without streaming to Wiim - ie. using a local renderer.

Responding to myself - I did a file transcoding of my DSD64 file with JRiver. Initially, it created 352.8 kHz files. Those started playing fine from JRiver MC without transcoding, with the Wiim Home app reporting 352.8 kHz. However, there were clicks and pops at the end of each track for about 2-3 seconds. This was unexpected. But the entire played through without white noise, nevertheless. So, there is some behavior in the on-the-fly transcoding that is different from the file transcoding. Not sure if it's a JRiver or Wiim bug, but either way I don't want to blow my ears, speakers or amp with the white noise, and I cannot use the on-the-fly transcoding again until the bug is fixed. Clearly no one has tested this before, or they would have run into it.
I just reconverted the DSD album to 176.4 kHz . It's playing fine now onto the Wiim Pro Plus, with no gaps, clicks, or pops. Seems that doing an offline transcoding is required for proper playback of DSD right now - very annoying.

 

[daydreamer]

Responding to myself - I did a file transcoding of my DSD64 file with JRiver. Initially, it created 352.8 kHz files. Those started playing fine from JRiver MC without transcoding, with the Wiim Home app reporting 352.8 kHz. However, there were clicks and pops at the end of each track for about 2-3 seconds. This was unexpected. But the entire played through without white noise, nevertheless. So, there is some behavior in the on-the-fly transcoding that is different from the file transcoding. Not sure if it's a JRiver or Wiim bug, but either way I don't want to blow my ears, speakers or amp with the white noise, and I cannot use the on-the-fly transcoding again until the bug is fixed. Clearly no one has tested this before, or they would have run into it.
I just reconverted the DSD album to 176.4 kHz . It's playing fine now onto the Wiim Pro Plus, with no gaps, clicks, or pops. Seems that doing an offline transcoding is required for proper playback of DSD right now - very annoying.

As I'm sure you're aware, off-line transcoding avoids the need for the WiiM to process DSD at all — you're converting DSD to PCM which makes your DSD material identical to any other PCM source as far as the WiiM streamer is concerned. It would be really nice if some kind of official handling of DSD material could be added to the roadmap!

 

[madbrain]

As I'm sure you're aware, off-line transcoding avoids the need for the WiiM to process DSD at all — you're converting DSD to PCM which makes your DSD material identical to any other PCM source as far as the WiiM streamer is concerned. It would be really nice if some kind of official handling of DSD material could be added to the roadmap!

Yes. Either offline or on-the-fly transcoding avoids the need for the WiiM to process DSD.
They should behave identically, but for some reason, they don't.
There's a bug somewhere, either on the WiiM or jriver side. I have brought this up to JRiver.
I will bring this up with WiiM too.
FYI, if I transcode on the fly to my Marantz SR7011 receiver, there's no white noise issue.

I already filed a ticket with WiiM about native DSD support.

 

[Giangi71]

WiiM Pro (not plus) isn't dsd decoder. Do I have to use on Roon dsd to pcm? Thanks a lot