Nice find. One thing to check before buying parts: the README says it works with line-level sources through a USB audio adapter. Most turntables output phono level, so unless yours has a built-in preamp (look for a PHONO/LINE switch on the back), you'll need a phono preamp between the deck and the USB adapter. Without it the signal is very quiet and has no RIAA equalisation, so it sounds thin.

Also, AirPlay buffers for a couple of seconds, which is fine for listening, but you'll notice the delay if you're standing next to the speakers while dropping the needle. The automatic start/stop on signal detection is the clever part for a turntable.