Let Roon upsample vs let Lumin T2 do the work


I've reluctantly invested in Roon for my Lumin T2.  I read somewhere to turn off all the processing in the Lumin app and let Roon do all the upsampling.  What's the benefit of that?  I figure my Lumin is built specifically for making the best signal possible. 

Secondly, my Roon core is an Asus ROG desktop computer, is it doing any work?  It's certainly not audiophile grade.
dtximages
DTX, Peter Lie, the head Lumin software engineer, specifically instructs to turn off upsample processing in the Lumin and utilize upsampling through Roon. "Real DSD" is simply a presentation of some music sources although I have yet to find any in my library or browsing. However, if "native DSD" is available the Lumin will process it. BTW, Erik was correct in his upsampling comment. I suggest you check the Roon website, "community" and peruse the Lumin hardware  section....lots of useful info there. 
Sorry. To the DAC, native DSD and upsampled DSD look the same, in that they follow the same format, and the DAC doesn’t know or care where it came from.
What I meant about "real DSD" was a recording released as DSD to begin with, or "native." Of course, from the data in the USB, fake (i.e. upsampled) DSD and native DSD look the same. I’m sure the Lumin handles them well.


But if you are upsampling, lets say from redbook (44.1kHz/16 bits) to 192/24 or DSD, you don’t get closer to the recording, you are fiddling with the DAC and output filters, and what is an audiophile except a knob fiddler? :)


But because of this "fiddling" there’s really no right answer about whether to upsample or not, and how. It’s very much in the range of personal taste.


I’ve tried DSD upsampling and with my setup (Roon / Mytek Bridge) the top end sounded harsh and unnatural, but 2x PCM sounds VERY nice indeed. Take a look at Figure 7 of this page, to get some idea of what’s’ changing:


https://www.stereophile.com/content/mytek-hifi-brooklyn-da-processor%C2%96headphone-amplifier-measur...


Of course, 44.1 kHz data cannot support a signal higher than 22 kHz, but in the 10kHz to 20kHz range you see some differences in how the data rate affects the filtering.
Looks like 192kb just plays higher with zero difference in the audible range.. I have no idea how to interpret that graph not being an engineer :)


Upsampling creates more steps and the analog conversion becomes much smoother. The real difference happens when there are any cliffs in the sound. In that case, more granular data due to upsampling provides better transitions and smoothness. 

 

Check this video - https://youtu.be/SdPU2TZylSs?si=uVxV-Lgu7yOjaEsx