turning a mac mini into an airplay receiver?

I'd like to turn my mac mini (running latest version of High Sierra as of today) into an airplay receiver. Is this possible to do? Basically I'd like to (a) connect it to my wifi network (b) connect it to a USB audio device and (c) have it appear to other computers/iphones/ipads on my network as a possible destination to stream audio to (e.g. in itunes).

I can do (a) and (b), but (c) is harder. Any advice?

Thanks!