I have a couple of RPi 3A+ connected via USB to D10s, E30 DACs.
Don't have any issue regarding SQ.
All those DACs are also using the same RPi USB port for power.
So here's my collection of Pi based music servers.
I'm running Volumio with a 64gb high endurance card in each, with my entire music collection stored on the cards (250+ CDs).
All of these units work well.
I'm reading the comments about problems with Pi 3 USB issues and people bumping their systems to Pi 4's and I just can't imagine why this is necessary. I have a Pi 4 available but just don't see the need to use it as a streamer. The audio quality on all of these units is fantastic.
One issue I did have with the PiZeros was that when trying to add new mp3 files to my SD Cards (mounting them from my laptop as an smb share and dragging the files to the, "internal" partition) I was getting an error that I was out of space, despite the fact that I showed nearly 30gb free. Supposedly, the latest repo of Raspian would automatically resize the partition of the SD card on first boot but for some reason this didn't happen.
This error only occurred on the Pi Zeros.
I never received an adequate explanation why this didn't work. Ultimately, I jumped through some hoops (using ssh to install raspi-config, advanced operations, resizing the partition) and now I have access to the entire 64 gigs of memory available and I can simply rip a new CD and drag the new music folder to the PiZero over my network. I'm guessing a 64gb SC card would easily hold 500 CDs worth of music.
Some people has freaked out that having the system and music on the internal SD card might wear out the card. Who cares? That's why I used a high endurance card which are rated at 5000 hours of continuous use and now selling for about $1). If I wear the card out - which I doubt I will - I have 5 backups on the other Pi's so I'll buy a new card and copy an image to the new card. No big deal.
On top of listening to my music collection, with this configuration, I can stream Spotify, Pandora, Tune-in, etc. and any of these units act as AirPlay nodes. I can also stream sound stream from my phone or tablet.
I must confess, watching a certain, "HB" YouTuber about how absolutely terrible the Pi's were with a cheap power supply I upgraded the Pi 3 to a fancy, switched power supply (rather than a $5 three amp wall wart). I'll be damned if I can hear any difference (improvement) over any of the others streamers. My feelings: $90 wasted. Save your cash.
Other thoughts: I love the Zero form factor. They are tiny, taking no space, are energy efficient and look really cool. The speed is quite adequate. Compared to the Pi 3 streamers, Zeros are a little slow but once you start a new stream and the music/ soundtrack has buffered, you really won't notice the speed difference again.
The 3A+ looks really cool, sounds great and is very fast. Too, it has a 5 ghz wi-fi radio so songs load very quickly when streaming from radio stations, Spotify, etc.
The 3+ Hifi Berry works great for me when I use it.
I can't tell any difference in sound fidelity between the units. They all sound great.
Wishlist: the Pi Foundation offers a 2 ghz Pi Zero and a sale on a lifetime Volumio passes.....
Bottom line: Get any model Pi streamer and I'm betting you'll really be impressed. Enjoy!
My collection of Pi Streamers:
(I'm mainly using the Pi Zero Allo, middle front, with RCA cables.)
(left front to right, rear)
Front
Pi Zero W w. Hifi Berry DAC + Zero
Pi Zero W w. Allo Mini Boss
Pi 3B+ Hifi Berry DAC +
Rear
Pi Zero W w. JustBoom Digi Zero Phat with S/PDIF optical output (note: ethernet connection)
Pi Zero W w. Apple Dongle
Pi 3 A+ w. Apple Dongle