These come with identical data but different electrical properties;
| TTL | 5 Vpp | 2 to 4 pin connector |
| SPDIF | 0.5 to 0.6 Vpp in 75 Ω | RCA |
| TOSLINK | Optical | JIS F05 |
With a good quality cable such as RG59 long SPDIF cables can be used. I recommend the use of BNC connectors in combination with BNC to RCA adaptors.