In January, Apple released tvOS 16.3, available for Apple TV 4K and Apple TV HD.
The tvOS 16.3 update can be downloaded through the Settings app OTA on Apple TV by going to System > Software Update. Apple TV users who have automatic software updates turned on will automatically be upgraded to tvOS 16.3.
According to feedback from users, Apple tvOS 16.3 unlocks the eARC feature. Apple Apple TV 4K has built-in eARC support. Pair it with up to two HomePod speakers to enjoy home theater audio on all your TV-connected devices.
According to the introduction, eARC (Enhanced Audio Return Channel) is an upgraded version of ARC (Audio Return Channel). It was introduced in 2017 as part of the HDMI 2.1 specification. eARC builds on ARC.
eARC builds on ARC. ARC greatly simplifies TV and home theater setups by enabling TVs to send audio to a bar or AVR over a single HDMI cable. eARC also allows TVs to use a single HDMI cable to send audio generated by built-in streaming applications, cables, satellites and other source devices (e.g., game consoles or Blu-ray players) to a bar or AVR. eARC supports much greater bandwidth and speed than ARC, so it can deliver high-quality, uncompressed audio.
The eARC supports a bandwidth of 37Mb/s and can transmit up to 32 channels of audio, including eight 192 kHz channels of 24-bit uncompressed audio. It also supports DTS-HD Master Audio, DTS:X, Dolby TrueHD, and Dolby Atmos formats. In comparison, ARC supports up to six channels of compressed audio with a maximum bandwidth of 1Mb/s.
