Streaming clarification

[audio_engr]

Hi All,

I'm using a Roon Nucleus (Gen-1) along with etherREGEN into my 440-Pro CI. 
My Roon Nucleus is set to perform all playback in DSD (as DSD64) using Roon's DSP function. 
And playback is using Roon RAAT. 

Question :  Which device is my Streamer ?  The Roon Nucleus or the Dev 440-Pro CI. 

Thank you !

- Arup

[Elztalbiker]

Nucleus stream to DEV.


Gesendet von iPad mit Tapatalk

[David A]

Arup,

A question. Why are you having Roon convert everything to DSD64 when the Devialet converts DSD to PCM before doing its digital to analog conversion?

Roon have a page on their website where they talk about upscaling and the reasons for and against having Roon upscale. One of the reasons for not having Roon upscale is that your DAC does a very good job of upscaling which results in no benefit being gained from having Roon do the upscaling. I've tried having Roon upscale PCM to 192/24 for streaming to my 140 Pro vs having Roon stream the music at whatever the native resolution is and letting the 140 Pro upscale and I don't hear a difference so I stream PCM at its native resolution and let the 140 Pro handle all upscaling.

I realise that converting PCM to DSD isn't simply upscaling but I can't see any advantage to converting PCM to DSD in Roon and streaming DSD to a Devialet where it is immediately going to be converted back to PCM before the Devialet can do anything with it. I'm not certain whether that conversion back to PCM is at 88.2 or 96 kHz or whether it's at 176.4 or 192 kHz, either way CD quality PCM is going to be upscaled by Roon before streaming to the Devialet but, as I said, I can't hear a benefit from having Roon upscale and I can't see a benefit in having Roon convert PCM to DSD when the first thing the Devialet is going to do is to convert DSD back to PCM.

Having said that, I do stream the DSD64 files I have on my Nucleus Pro to the 140 Pro as DSD and let the 140 Pro do the DSD to PCM conversion.

I'm not saying that what you're doing is wrong or sounds worse, I'm just wondering why you choose to stream in this way.

David

[markush]

Hi David,

many have observed that when Roon or depending on setup other devices are doing the upscaling it results in a better audio performance. Maybe this is due to less electronic noise created within the Devialet when it’s not needing to do (heavy) calculations.

As we know the Devialet is in general very sensitive to power, noise etc. but if done right has a very good potential to unfold.

[Vivialet]

I use the Roon upsampling because I also use Roons convolution engine with Focus Fidelity filters. Roon does the upsampling first, so the convolution takes place with a much higer resolution in most cases.
I think this sounds better, at least with 44khz source files.

[David A]

@Vivialet : I can see that there may be a benefit in your case since you're combining another DSP function, convolution with the Focus Fidelity filters, with the upscaling.

@markush : caveats accepted.

I repeat: I was not suggesting that Arup was doing anything wrong. He and I have exchanged personal messages in the past about some other issues and I respect his opinions. I was simply wondering why convert PCM to DSD prior to streaming when the first thing the Devialet is going to do is to convert the DSD stream back to PCM. On the surface that amounts to performing 2 digital processing operations which cancel each other out so it seems as if there's no reason to make the initial conversion. I'm guessing that when the DSD stream is converted back to PCM by the Devialet it's not converted back to PCM at the original sampling rate, at least for files which were originally CD quality. I suspect the reconversion to PCM results in a 192/24 stream, or perhaps even a stream at the higher sampling rate at which the Devialet's DAC operates. I was wondering whether Arup is noticing something there which I hadn't noticed.

And, of course, with his system including a 440 Pro whereas mine includes only a 140 Pro, and adding in my 75 year old ears which I suspect have a little more "wear and tear" on them than Arup's do, he may very well be hearing something I won't hear. I asked my question because I'm interested in hearing his reasons for his choice and I asked here rather than in a PM because I think that if I'm interested in hearing his reasons for his choice there may well be others here who might find something interesting in his answer as well.

[David A]

To add to my message above.

I have a number of sites I check daily including a couple of Roon forums. After finishing my reply above I checked the Roon Devialet forum and found a new thread just started by someone who is doing essentially the same thing as Arup is doing. His post includes screen shots of his Roon settings. Here's a link to that thread:

https://community.roonlabs.com/t/deviale...tup/234408

[audio_engr]

Arup,

A question. Why are you having Roon convert everything to DSD64 when the Devialet converts DSD to PCM before doing its digital to analog conversion?

Roon have a page on their website where they talk about upscaling and the reasons for and against having Roon upscale. One of the reasons for not having Roon upscale is that your DAC does a very good job of upscaling which results in no benefit being gained from having Roon do the upscaling. I've tried having Roon upscale PCM to 192/24 for streaming to my 140 Pro vs having Roon stream the music at whatever the native resolution is and letting the 140 Pro upscale  and I don't hear a difference so I stream PCM at its native resolution and let the 140 Pro handle all upscaling.

I realise that converting PCM to DSD isn't simply upscaling but I can't see any advantage to converting PCM to DSD in Roon and streaming DSD to a Devialet where it is immediately going to be converted back to PCM before the Devialet can do anything with it. I'm not certain whether that conversion back to PCM is at 88.2 or 96 kHz or whether it's at 176.4 or 192 kHz, either way CD quality PCM is going to be upscaled by Roon before streaming to the Devialet but, as I said, I can't hear a benefit from having Roon upscale and I can't see a benefit in having Roon convert PCM to DSD when the first thing the Devialet is going to do is to convert DSD back to PCM.

Having said that, I do stream the DSD64 files I have on my Nucleus Pro to the 140 Pro as DSD and let the 140 Pro do the DSD to PCM conversion.

I'm not saying that what you're doing is wrong or sounds worse, I'm just wondering why you choose to stream in this way.

David

Hello David,

It's been a while since our last communication. 

I go DSD in Roon because I evaluated very critically [native PCM to Devialet] vs. [DSD64 to Devialet] and I found that with DSD, phasing was much more accurately rendered and it was most appreciable with classical orchestral music. The orchestra was precisely placed within the soundstage and the soundstage was also like real life, i.e. wide and deep with precise height. Further, DSD rendered superior low-midbass-mids better to my ears. 

Indeed, the BB 1792 dacs inside our Devialets will work as PCM thus the DSD files sent to Devialet ultimately becomes PCM and in fact ADDS more processing steps along the way than directly sending native PCM to Devialet and let Devialet upsample (if it wishes) but again ... to my ears, the DSD route sounded more correct. And since 2021, I've gone the DSD route.

Thanks for your detailed clarification that helps me to understand that our Nucleus is the streamer. By the way, Uptone Audio's etherREGEN is almost thro' with their GEN-2 which is promised to be waaaayyyy superior to what we use.   

Thanks again !!

- Arup

[audio_engr]

To add to my message above.

I have a number of sites I check daily including a couple of Roon forums. After finishing my reply above I checked the Roon Devialet forum and found a new thread just started by someone who is doing essentially the same thing as Arup is doing. His post includes screen shots of his Roon settings. Here's a link to that thread:

https://community.roonlabs.com/t/deviale...tup/234408

This is exactly what I've been doing since 2021. 

- Arup

[David A]

Arup,

Many thanks for the reply. You convinced me to try it but I've gone back to streaming PCM as PCM at its original resolution.

The first thing I noticed when I tried the DSD conversion was the drop in level. I'd been expecting the 6 dB drop associated with the DSD to PCM conversion in the Devialet, I deal with that when I stream the DSD64 files I have on my Nucleus+ to my 140 Pro, but I'd forgotten about the 3dB loss in the Headroom settings which I also copied from that post on the Roon forum.

Once I had the level back up to my usual listening level I had mixed feelings. I don't play classical very often and rarely orchestral music. Mostly I play small group jazz. I put on an album by Viktoria Tolstoy, a 96/24 high res download and tried that. I thought that everything sounded cleaner but "too clean" in a sense. One of the things I like about my system is how natural voices sound, especially the sense it delivers of voices coming from breath. Tolstoy's voice lacked that sense of breath and I thought the sense of chest tone had diminished. I liked the cleanness of the sound, the voice sounded a little sweeter as a result, but that added sweetness came at the cost of losing my sense of her as a breathing person. As a result I lost some of the sense of "naturalness" that I like and that's not a price I like paying, even if things sound a little sweeter and cleaner in some ways.

I'll add a caveat to that comment. There's a part of me which thinks that what I should do is to live with the change for a week in order to get used to it because when I do that I stop hearing the differences and I start hearing the sound that I'm getting. I need time to become accustomed to a change in sound so that I can appreciate the change for what it offers rather than simply noticing what it changes. When I make changes I usually go that way but with some changes, and this was one of those occasions, I seem to have an immediate reaction which causes me to put things back the way they were. I've learnt over time that I can usually trust those reactions. I may try it again in a day or two and try to stick with it for some days but at the moment I don't want to do that. I'll see if I still feel the same way in a couple of days after letting what I heard work on my subconscious in the background.

At present I can understand why someone might like and prefer converting PCM to DSD before streaming to the Devialet, it does have some attractions for me, but those attractions seem to come at the cost of the loss of something else that I really like.

RE the EtherREGEN 2: on of the changes is that the single ethernet port on the B side is going to be a gigabit port rather than a 100T port. That concerns me. I'm still not convinced that Devialet have completely solved the RAAT/ethernet problem and Devialet's last recommendation on that issue was to use a 100T connection to the Devialet. That 100T port on the current model is one of its big attractions for me. Most of the time I'm running RAAT over ethernet without problems but for some reason every now and then I seem to have a week or so when the RAAT connection keeps dropping in and out and my network connection between the Nucleus and the Devialet becomes unstable. I turn things off and back on and eventually things go back to being stable again for months. It's frustrating because I can go into Roon's Audio settings menu and I can see the Devialet available for Airplay and also for connection using Devialet's own AIR protocol but the Roon Ready connection just doesn't show. Even worse, I can sometimes see it come back into existence in Roon's Audio settings menu and then just disappear again a couple of seconds later on occasion. I'm reluctant to go back to using a gigabit connection to the Devialet while this sort of problem still exists, even if it is sporadic and only occurs at intervals of several months.

David