Coaxial S/PDIF

Coaxial S/PDIF (Sony/Philips Digital Interface Format) transmits digital audio over a single 75-ohm coaxial cable, terminated with an orange RCA connector. It carries the same bit-perfect digital signal as optical Toslink but has technical advantages.

Coaxial vs Optical

• Coaxial – lower jitter, higher bandwidth (up to 24-bit / 192 kHz), no light-to-electrical conversion
• Optical – galvanic isolation (no ground loops), can’t pick up electrical interference

For most listeners at reasonable cable lengths, both sound identical. Long cable runs favor coaxial. Ground loop problems favor optical.

Where you’ll find it

AIYIMA A80, Fosi Audio S3, and most streamers have both coaxial and optical S/PDIF – use whichever your source has.