Is PCM to DSD conversion a lossless process

Roon Software Discussion
41

Apologies for resurrecting this old thread but I now have an Auralic Sirius that can convert pcm to dsd. Reading through the above there is a lot of conversation about dsd to pcm and perhaps it not being such a good idea.
My question is the other way around. Is there any benefit to be had from converting pcm to dsd. The suggestion so far from the internet is that the conversion may add a greater sense of high end treble, even sibilance? Why?

42

Really, in matters like this why take someone else’s opinions?

Listen for yourself and decide. It isn’t irreversible.

43

Thanks.
I have a 7k Sirius on demo. I may just listen before deciding, but it’s an expensive mistake to make if my noticing a difference is based on my new ‘ excitement’ bias.

1 Like
44

Why indeed? Sounds like nonsense to me. Believe everything you read on the Internet!

45

I hope it is more than for just a day or two. Imho, audio equip. needs to be listened to in the environment it is going to be used. Especially if buying it and not liking it would be an “expensive mistake”.

If I’m reading right, then the Sirius is NOT a DAC but a Digital Audio Upsampler. And, imho again, if that is the goal, I would and do use HQPlayer. Same reason I wouldn’t even think about the Chord M Scaler. It is not just about going to the higher rate, but, how you get there. It is ALL about the modulators and filters used in the upsampling.

I can’t speak for the Sirius, but, in HQPlayer taking PCM to DSD 256 or 512 using ASMD7ECV2 is fantastic.

1 Like
46

Oh, everything.
I read somewhere that the US election was a fraud, and that there’s a bus on the moon.

47

First thought: Having this device on hand you may actually compare at least several options on your system (these are immediately available as long as you are using ROON):

  1. ROON bitperfect into your DAC
    vs
  2. ROON upsampling to PCM or to DSD into your DAC
    vs
  3. ROON bitperfect into Sirius and Sirius upsampling to PCM or DSD into your DAC

For the above testing I would select multiple PCM sources that differ in a) bit rate 44/48/96/192 etc… b) genre (jazz, classics, rock, electronic) This combination would normally flash some strengths and weaknesses…

  1. Equally, echoing @Rugby, having this device on hand it is a great opportunity to also compare this with HQPlayer software (it is free to test)

Second Thought: reading the description of Sirius, I can not see anything very special for it’s hefty price tag. USB Audio Output - up to 384K/32bit for upscaler ? Oh, c’mon ! Native DSD512 over USB is good (but not special) and comes with certain caveats, i.e. requires “Linux compatible DAC” (well, not unusual). The main question is - how powerful would AURALiC Proteus G2 platform be for PCM to DSD upsampling - the process which is known to require significant computation power. In my limited read on “Proteus” it seems that, say, simple 8i7 NUC could be more powerful.

“Third Thought”: to stay on topic. PCM to DSD conversion is lossless, but is a bliss when done correctly. Below can be achieved at the cost 7 (seven) times less than of Sirius. I’m ready to bet that none of the hardware upscalers at any price today can do that:

image