🔶 Coaxial (RCA) SPDIF:

  • Uses a copper wire inside a coaxial cable.
  • Has an RCA connector (looks like those red/white/yellow plugs).
  • Carries electrical digital signals.
  • Requires a 75-ohm impedance cable for proper SPDIF transmission.

S/PDIF

https://en.wikipedia.org/wiki/S/PDIF

S/PDIF (Sony/Philips Digital Interface)[1][2] is a type of digital audio interface used in consumer audio equipment to output audio over relatively short distances. The signal is transmitted over either a coaxial cable using RCA or BNC connectors, or a fibre-optic cable using TOSLINK connectors. S/PDIF interconnects components in home theaters and other digital high-fidelity systems.

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