Streaming through Roon - DSP/ upsampling considerations?

[zambie]

OK, I'll toss my hat in the ring since I have tried DSD and upsampling with Roon.

First, don't get Roon to convert DSD to anything higher than 24/192 or upsample PCM to anything higher than 2 4/192. If you do then Roon is just going to downsample it to 24/192 anyway because that's the highest rate the Devialet can accept. That's extra processing and unnecessary hard work on the processor running Roon, and in theory 2 DSP operations where the 2nd one is a reprocessing of the first one might introduce errors that you don't get when you just do a single processing operation to the final result. I said "in theory" because any difference may well not be audible but basically, why do twice the work when half the work will do?

Second, I've tried both DSD conversion and upsampling in Roon. I couldn't really notice a difference in sound quality compared to sending DSD or PCM at its native bit rate to my 140 Pro. I turned of DSD conversion and upsampling in Roon. Interestingly Roon themselves suggest that if you have a high quality endpoint which can do these functions you may be better off letting the endpoint do these things because the manufacturer of the endpoint may well have tweaked their product to ensure it delivers the best results when doing this sort of processing. Once again, turning it off takes some processing load off the device running Roon and, depending on what you're doing, there can be quite a bit of processing involved. My advice would be to try it if you want to but if you don't hear a difference then let the Devialet do these things for you.

Third, how are you getting the signal to your 220? If you're using the 220's ethernet input and you're using the Roon Ready protocol (RAAT) with a gigabit speed connection, then don't set Roon to do any upsampling/DSD conversion. There's a bug in Devialet's software for people using RAAT causing playback to stop for periods. It does not affect everyone but some people get it often and some people get it rarely and high res input seems to make it worse. I rarely get the problem if I have Roon send  my content in bit perfect mode (no upsampling) but if I have Roon up convert to 24/192 I get the problem often. This bug isn't present if you're using the wifi input on the Devialet or if you're having Roon use the Devialet AIR protocol. Some people prefer AIR, some prefer RAAT. I prefer RAAT so I don't do any upsampling in Roon. Another way of avoiding the bug if you use ethernet and RAAT is to ensure that your ethernet switch or router feeding a signal to the Devialet slows the signal from gigabit speed to 100T speed.

In the end I found no advantage to having Roon do any processing of the signal but you can try it for yourself and see if you agree. Just don't process to a higher resolution than 24/192 since there's no point in doing so and if you're using a wired gigabit speed ethernet connection be prepared to have playback problems because of the bug in Devialet's software.

This is super interesting input David - appreciate the details. I'm using the ethernet input as well as leveraging RAAT. Wireless has been very difficult to establish especially while streaming hi-res files, so have opted to keep ethernet. I have had a couple of drops /pauses on files - not often but 1-2 times in a 2-3 hr listening session. 
I'm inclined to agree (just on matter of principle) that 24/192 upsampling makes sense. Anything above, doesn't make sense given that the devialet hardware will bring it down to 192.
Will continue some experimentation and see where the sweet spot lies for me. Thanks!