eARC (Enhanced Audio Return Channel) is the next generation of ARC. eARC is being implemented as part of HDMI 2.1 specification. eARC gives a big boost in bandwidth and speed when high quality audio is sent from your TV to a soundbar or AV receiver.
The eARC is a feature implemented in the latest HDMI 2.1 specification . If your TV is HDMI eARC enabled, but your AV amp or soundbar is only compatible with HDMI ARC, it's likely you'll get a sound - but the bandwidth restrictions of ARC will mean you won't be able to experience the high bitrate audio that eARC can provide .