Audio Return Channel or Optical Audio for Dolby Digital Sound?

Home Cinema Guide may get a commission if you buy from a link marked with * on this page: about ads
By: Santiago Barriocanal (Asuncion, Paraguay)

I have my Blu-ray player connected to the TV with an HDMI cable, and the receiver is connected to the TV. Thanks to the ARC I can hear thru the receiver what I watch on the Blu-ray player. I was watching a DVD (with the Blu-ray player) the other day whose audio was in Dolby 2.0, however, the receiver won’t show that the signal is Dolby.

However, if I connect the Blu-ray player with an optical (digital-in) cable, the receiver detects that the sound is Dolby, but the sound is not as loud as it is with the ARC (which won’t detect that the sound is Dolby).

It’s a mess, but I hope it’s somehow understandable. I would like to know why is that please and which way is better for instance when I have a 5.1 movie, should I use the optical or the ARC function?

Comments for Audio Return Cha‚Äčnnel or Optical Audio for Dolby Dig‚Äčital Sound:


Firstly, the ARC (audio return channel) function is really meant to be used for sending audio back to your receiver from devices which cannot easily be connected directly to the receiver. For example, for the TVs built-in digital (or analog) tuner that receives broadcast TV via an aerial (or antenna).

Therefore, if you have a Blu-ray player, you would usually be better connecting it directly to the AV receiver. Something like this:

Connecting a 5.1 home theater system with an AV receiver
Connecting a 5.1 home theater system with an AV receiver

This allows the receiver to do what it is best at – decoding the different types of audio signals and sending them to the speaker system.

Your TV is unlikely to have full decoding capabilities like your receiver, and so it is not surprising it isn’t handling the Dolby Digital signal very well. I would guess that the TV will just be converting the Dolby Digital signal to stereo PCM and sending this to the receiver via ARC.

It’s not clear from your question if you are getting surround sound audio formats from the Blu-ray when using ARC. Is the problem you are having just with stereo Dolby Digital?

The ARC feature should be capable of passing through a Dolby Digital signal, but it doesn’t surprise me if you are having problems when connecting your devices this way. It may be that the TV will only pass through Dolby Digital from the internal tuner – and not from external devices connected to the TV (like your Blu-ray player).

If you want to be sure of the capabilities of your TV, check the manual, or call the manufacturers helpdesk. Also, make sure the firmware of the TV is up-to-date as there may be issues with the ARC which have been identified and fixed since you bought the TV.

However, in your case, I would just connect the Blu-ray player directly to the receiver and then you will be able to hear the best audio available. An HDMI connection would be the best type to use, however, if your AV receiver doesn’t have HDMI then the optical connection will be fine.

Hope that helps.

Paul (Site Editor)

You Might Also Be Interested In:

Home Theater Connections Guide

Best AV Receivers: Top 13 Reviews & Buying Guide

Dolby AC-3, LPCM and DTS 5.1 – Blu-ray Audio Codecs Explained

home cinema guide logo

About The Author

Paul started the Home Cinema Guide to help less-experienced users get the most out of today's audio-visual technology. He has been a sound, lighting and audio-visual engineer for around 20 years. At home, he has spent more time than is probably healthy installing, configuring, testing, de-rigging, fixing, tweaking, re-installing again (and sometimes using) various pieces of hi-fi and home cinema equipment. You can find out more here.

Home Cinema Guide may get a commission if you buy from a link marked with * on this page: about ads