What is the purpose of S PDIF?
S/PDIF (Sony/Philips Digital Interface) is an audio transfer format interface. It transfers digital audio signals from one device to another without the need to first convert to an analog signal, which can degrade audio quality.
Does RPI have audio in?
Raspberry Pi boards are capable of recording stereo audio using an interface called the inter-IC sound (I2S or I2S) bus. The I2S standard uses three wires to record data, keep track of timing (clock), and determine whether an input/output is in the left channel or right channel [read more on I2S here and here].
Can you use a Raspberry Pi as a DAC?
The Raspberry Pi DAC Pro is compatible with any Raspberry Pi computer that has a 40-pin GPIO header. Features: Power LED. Analogue out (0–2V RMS via P7)