HDMI with ARC

[utomo]

Audio Return Channel[/b] (or ARC for short) is a feature of the HDMI specification (first appearing in v1.4, released in 2009) that allows you to send audio "upstream" from your TV's HDMI inputs back to your audio system's HDMI output in order to listen to the TV's internal audio sources, like smart TVapps and tuned over-the-air channels

http://hometheaterreview.com/everything-you-need-to-know-about-arc-audio-return-channel/

I think it is good features, but It look like I mostly did not see it on most projector.
can somebody explain why ? mostly people did not know/ need or price ? I think it is not expensive right ?

 

[bigboss]

The majority of projectors don't have in-built speakers. If sound does not get to the projectors, why would you need ARC?? There's nothing there to return.

 

[The_Lhc]

Plus ARC is of most use when using the inbuilt tuner in a TV, something projectors don't have.