S/PDIF (Sony / Panasonic Digital Face)
S/PDIF connectors can either be a coaxial connector or more commonly a fibre optic connector.
Connect the cables between the TV and the sound system.
Adjust the volume on the sound system to the desired level. Some TV may still play audio out of their native speakers. Turn the volume on the TV down to zero so the sound system is the only audio output.
HDMI ARC (Audio Return Channel)
HDMI ARC uses an HDMI input on your TV to communicate back and forth to your sound system. It has the advantage of smart controls which can allow you to control your sound system with your TV remote, simplifying your system.
Plug your HDMI cable into your sound system and into the HDMI port on your TV which has ARC capabilities. Refer to your TV specifications for this information. Most modern TV's use HDMI port 1 as the ARC capable port.
An Auxiliary connection typically uses a 3.5mm auxiliary cable to send a raw audio signal to your sound system.
Plug the Auxiliary cable into your sound system and into your TV, usually, the Auxiliary port is denoted by the Headphones symbol.
Adjust the volume on the sound system to the desired level.
Typically when an Auxiliary port is plugged in the TV will not play audio through the speakers. If you want to play audio from your TV and not the sound system you will have to unplug the Auxiliary cable.
NOTE: Some TVs provide the option to play audio through the TV's speakers and the Auxiliary port simultaneously. Explore the TV's settings to identify this capability.