Audio output guidance / embedded hifi audio player

[Nicolae Vlădescu]

Hello.

I am just getting started with my bbb but i can't seem to wrap my head around the I²S protocol.

From what i managed to gather bbb can output audio via usb versus for example raspberry pi that has special I²S headers on the board.

I want to transform my bbb into an hifi audio player using runeaudio or volumio, but i can't seem to find any suggestion on what hardware should i use, is it a cape? an usb soundcard (cheapest), usb dac, usb dac with preamp or the more expensive usb audio interfaces?

What is the recommended hardware to take advantage of the full I²S protocol on bbb?

Thank you.