I am setting up a dedicated music server and using Roon is one of the main reasons to do so. I am a bit puzzled by conflicting views on the relative importance of different stages of the chain and would welcome some advice. In particular:
If I build a server outputting bitperfect audio, is there anything else that can improve on audio quality at this stage, prior to endpoint and DAC? In other words, what makes a SonicTransporter or a Streamplayer or a Nucleus different from each other, to the extent that they achieve bitperfect output resolution?
Similar to my previous question, is there any significant difference between a Raspberry Pi-based endpoint running, for example, RoPieee, compared to commercially available (and often much more expensive) endpoints? Anything that I need to look out for?
I will hook the Roon Core and the Endpoint to a McIntosh C50 preamp, going to a Pass Labs X250.5 final amp. Is there any way that Roon can be made to control the volume of the C50, or anyway the final volume? If yes, ios it through the DAC or through the preamp? I am not aware of any way to control the volume of the C50 outside of its own remote or a RS232 interface.
I’ll give input on this one, as I know there will be a lot of input on the other two points.
Yes, you can have Roon perform digital attenuation before the McIntosh. So the signal is attenuated prior to the DAC in the Mac. HOWEVER, you may not want to do it that way. One way to look at it is you want to control volume on the device that has the best quality attenuator. Your McIntosh will be very good at that. It can also be done in the digital domain in Roon. But if you need a lot of attenuation you start trading off resolution in the signal. Since you have some hefty amps, this could be significant.
Roon does all this in a pretty sophisticated way, so I don’t know you could predict the differences. But fortunately you can use your ears to judge.
It would be better to be able to have Roon talk to the DAC/Preamp and have the DAC/Preamp make the adjustments. It can do this with my MSB Analog DAC which is Roon Ready. I don’t believe the McIntosh is, so you’d likely need to have Roon do the digital attenuation.
The main issue to look out for is that the connection to your audio gear (DAC or integrated) USB, S/PDIF coax, or AES is an electrical connection, and as such it can carry stray electrical noise into the innards of your audio gear. This noise does not affect the digital music coding directly, but it can affect the digital-to-analog conversion or downstream low-power analog circuitry. DACs vary a lot in their ability to filter out that kind of noise, or they may do a great job for one type of input such as S/PDIF coax and not so well for another type of input such as USB. Unfortunately, with so many variables it is hard to give a hard-and-fast recommendation. One thing that seems to be somewhat supported by evidence is that Pi USB ports are quite noisy electrically and can affect a range of DACs. But even then there are analyses that show good Pi>USB>DAC combinations.