earc

eARC, or Enhanced Audio Return Channel, is an HDMI feature that enables high-bandwidth audio to travel between a television and an external audio device such as a soundbar or AV receiver over a single HDMI connection. It is an evolution of the original ARC (Audio Return Channel) and was introduced with the HDMI 2.1 specification. Both devices must support eARC for the full feature set; otherwise, devices may fall back to ARC.

eARC provides significantly higher bandwidth than ARC, enabling uncompressed and high-quality audio formats to be transmitted. It supports multi-channel PCM up to high sample rates and bit depths (up to 7.1 or 8 channels at 24-bit/192 kHz) and can carry lossless formats such as Dolby TrueHD and DTS-HD Master Audio, as well as object-based formats like Dolby Atmos and DTS:X, typically either as bitstreams or decoded to PCM by the receiver. In addition, eARC includes improved lip-sync correction and simpler control via HDMI-CEC.

Setup typically involves connecting the TV and audio device with an HDMI cable and selecting eARC as the audio output on the TV and the corresponding input on the sound system. The connection is backward compatible with ARC devices; when only ARC is available, the system will operate with the older standard. Users should ensure both devices are updated to firmware that supports eARC and use a cable capable of the required bandwidth.