Audio Return Channel (referred to from here as ARC), is the option to send audio from a Display upstream to an Audio Playback Device over a single HDMI cable. This can be done without an external source and audio-transmitted from a Display's internal apps.
While ARC may support higher bandwidth audio signals than previously capable via Toslink and Analog transmissions, it cannot transmit uncompressed audio such as Dolby TrueHD. However, hope is not lost for the home theatre enthusiast with an older system as a format of DD+ Atmos can still be transmitted over ARC.
Recent revisions to ARC have brought forth Enhanced Audio Return Channel (referred to from here as eARC). eARC allows for uncompressed High Bit Rate Audio Formats, such as Dolby Atmos and DTS:X, to be returned to Audio Playback devices bringing true cinema-grade audio into the home without all the external devices.
The only issue with eARC? It may require you to buy a new cable. Bullet Train provides a variety of HDMI cables capable of supporting the high bandwidth of uncompressed audio, while supporting video beyond 4k.
Still using ARC or Toslink?
Bullet Train cables also support ARC. If the need arises to extend Toslink or ARC over distance, AVPro Edge offers solutions to extend either up to 330ft over category.
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