As usually , I would like to say ,thx you Amir , for your time and effort . The audio world has changed and Amir is one (main) of the driving forces .
Now getting back at Boss2. For a long time , earthing was a big part of audio . With XLR outputs it becomes less important (but still relevant). With the correct earth , RF has a path to escape . Some of you will argue that its not important , but in all my test data , I see a clear improvement with earth. Therefore all our power supply , DACs etc have a way (and some multiple) to earth using various C+R values .
Earthing is not standard . What works on one system might not work the same , on a different location . Again , this is why we have a DC earth (Nirvana SMPS) but also an earth lug on both Nirvana and Boss2 (for direct connection )
Boss2 has also multiple ways to power it, you can use one DC power (both Boss2 and RPI4) or use 2x PSU one for Boss2 and one for RPI4 (with the GND shared of course). I will not comment on "how it will sound" but from what I remember we got slightly better THD+N
About our company . We are a canadian company that has a R&D center in Bangalore India and a smaller one in EU . We work as a team and we are proud of our work .