My Pis have been mating like bunnies - I now have 3 going into my Marantz SA8005. My tunes are on an external USB drive going into a PC - no NAS. Mostly Redbook, some HiRez, no DSD (barely). I already had Ethernet going to the system so I added a 5-way switch near the rack to feed the Pis.
1) Rasp Pi II, with Hifiberry Digi+: This guy runs Moode Audio. I don't really neeeed this one, but I really like the Moode interface and how it is so sweet to select among the various pre-programmed (100? 200?) radio stations. At this time I only use it for internet radio. It's the only way I can get the fantastic Czech classical station, which broadcasts in better-than-cd quality (16/48) to my main rig. There are many stations broadcasting at 320K, and even the ones at 128 are very listenable. If I get around to it I'll map Moode to the USB drive so I can get to all my music to it. Or, I can just pop my backup USB drive into it and have a cute lil' MPD-based server. Moode can resample, so I usually bump everything to 192K, cuz why not? I use the optical out on this guy. Using a 2.5A CanaKit switching pwr supply.
2) R Pi III, with no other board, so USB out only. No wireless used. I currently have the demo of HQPlayer on this guy. I recently upgraded my PC as part of this nefarious plan, so I have no problem doing any of HQPlayer's advanced filtering/upsampling/DSD conversion. I'll probably use this one to upsample everything to 2X DSD. The HQPlayer interface is pretty primitive so this setup is for the really serious listening. Sounds great. Using a Jerome linear pwr supply I used to use w/ my Touch. [edit - using this as an HQPlayer NAA device]
3) R Pi III. w/ Digi+. No wireless used.: This guy runs PiCorePlayer, an excellent program that turns your Pi into a Squeezebox. This Pi is now integrated with the 4-5 other Squeezeboxen around the house, so it fits perfectly into the ecosystem my wife is used to. PiCorePlayer allows for an unholy range of filtering options. Linear or minimum phase? Bah humbug - You can pick, from 0 to 50 , exactly how much linear or minimum phase behavior you want. Many many more "behind the scenes" options, which made me realize that we don't listen to the sound of a dac as much as listen to the filtering choice the designer made (oversimplification but good food for thought...). I find Tidal works well through this Pi so when I re-do my subscription I'll use this Pi for Tidal. Got a nice beefy metal case for this one (seen on Hifiberry site). Using a 2.5A CanaKit switching pwr supply.
Now, I know you are all saying Mike Mike Mike why don't you just buy a microRendu, which will do the Squeezebox, DLNA and HQPlayer thing with one box? Well, its $700 for a teeny-weeny computer but is supposed to outperform the Pis handily. Oh well, maybe someday. I think I can turn some of these Pis into DLNA devices, so I could plumb JRiver to them too.
And you are also saying Mike, why don't you just use Roon to control HQPlayer? Well, that's $500. See a theme? Going for bang and fun for the buck lately.
That's the setup for now. I will gladly help anyone with any questions, although I am no expert (I just know how to use Google)
Its important to say that I DO NOT KNOW LINUX!! NONE of the above setups have required any Linux knowledge. You just need to know how to download, unzip, and copy the pre-made Linux image files onto a micro SD card.
Fun. New music. Win.
-Mike