norns-shield VS rtaudio

Surface mount soldering is not too hard. I can't view the BoM on mobile, but from the photos the soldering looks achievable for someone with experience soldering through hole. Take a look at the document here https://github.com/monome/norns-shield/tree/main/bom - if it's mostly 0805 sized components you should be fine. Even a few 0603 would be okay if you have good vision and a steady hand.

It's on Github

The pcb is available at pusherman. The important parts are in stock at mouser, here's the BOM. The audio codec was hard to find for a long time, but it's available at the moment. I think you would need to substitute a capacitor or two. Monome's github has a lot of good information (e.g., schematic) and here is some helpful information on assembly. There are tons of helpful people on lines.

for an example - you may want to look at the open source synth project that our friends over at monome did a while back .. github repo, docs, BOMs, etc are here .. but that's a full featured synth programmable / customizable with lua on a rpi with a CS4270 DAC - quite a few musicians involved in that community .. fun project

I used the bom and the markings on the pcb. The mechanical parts are described on their github : https://github.com/monome/norns-shield

They could have used RtAudio.cpp/.h from STK, audio support that works on Linux, Mac and Windows. See https://github.com/thestk/rtaudio/blob/master/RtAudio.cpp