HDMI ARC Questions - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 10 Old 02-09-2014, 03:15 PM - Thread Starter
Member
 
DrGregC's Avatar
 
Join Date: Jan 2006
Posts: 87
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 12
There is much written on this topic on the forum, but it is all very confusing. I need fact vs. opinion concerning the usefulness of the HDMI ARC protocol in connecting a soundbar and television. Thanks.

  • Compared to an optical connection (currently 2.1, PCM, if I understand correctly), wouldn't the HDMI ARC connection allow for better sound and true 5.1 compatibility?
  • Is the ARC protocol standardized? Is there a problem connecting a Samsung TV (with ARC) to a Sony soundbar (with ARC)?
  • What are the disadvantages of using the HDMI ARC connection between a TV and a soundbar?
DrGregC is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 02-09-2014, 07:15 PM
 
ttlnb's Avatar
 
Join Date: Aug 2004
Posts: 433
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 47
HDMI is a complicated beast and while there is a standard very few manufacturers submit their products for testing. To understand ARC you have to understand how HDMI communicates. Before I go any further both ARC and optical connections are capable of 5.1 signals. Whether they use them is a different story.

In the HDMI chain the source is the master and controls what is sent. Everything has to authenticate itself to the source. So your cable/satellite box, Blu-ray player, apple TV, game machine etc. are the master in your system. The display has to authenticate with the master and here is where the problem with ARC and optical connections from the TV might only send 2 channels of information.

The TV authenticates with the source and states it is a stereo device. The source also know there is no receiver in the chain so it sends a stereo signal to the TV. The TV connected to a receiver or sound bar via either ARC or an optical connection passes along the stereo signal. So you do not receive 5.1 information. So for the TV to pass a 5.1 signal it has to identify itself as being capable of receiving a 5.1 signal. For TVs to receive a 5.1 signal they must have a 5.1 decoder in them.

That is why ARC or optical might only get 2 channel PCM because the TV is identifying itself as a stereo only device. Depending on your equipment you may or may not get a 5.1 signal. A better solution if your sound bar or receiver is capable is to connect all your sources to them and then run one HDMI cable to the TV. If the audio device is in the middle of the chain it will be identified by the source as being capable of multichannel sound. Also, you can receive lossless audio. Something that is not possible through either ARC or an optical connection with 5.1 or 7.1 sound.

Beside ARC not being able to receive lossless audio another disadvantage is to use ARC you have to turn on the CEC function of HDMI. CEC stands for consumer electronic control but each manufacturer uses its own name for it. Here are some.

Panasonic - Viera Link
LG - simple link
Sony - Bravia sync
Samsung - Anynet

Anyway, what CEC is supposed to do is turn on the devices needed, switch everything to the correct input and have the volume control work for the system. So for example you are watching TV and then turn on your Blu-ray player. The TV and your audio device switch to the correct input (and turn on if off), your cable box shuts off and the volume button on your Blu-ray play now controls your audio system. Well, this is an area where manufacturers use different codes for different functions and these things do not play nice together. Even devices of the same brand I often can't get to work with CEC. With VERY few exceptions it is probably just better to not use it.

If I were to give some general advice. Do not use CEC and ARC, turn them off in all your devices. Connect your sources to the audio device if it can do HDMI switching and then connect and HDMI from the audio device to the TV. If not run separate audio cables to the audio device and HDMI to the TV. Get a decent universal remote to control the system, they are not that expensive. If you follow this simple advice you will have lossless sound, good control of the your system and will decrease yours and your family's frustration.
HDMI Guy and alanjmartiin like this.
ttlnb is offline  
post #3 of 10 Old 02-09-2014, 08:27 PM - Thread Starter
Member
 
DrGregC's Avatar
 
Join Date: Jan 2006
Posts: 87
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 12
Thank you, ttlnb. Brilliant answer! You have completely answered my concerns. I will run my source HDMI connections to my soundbar and send the output of the soundbar to my TV by HDMI. Correct?

I have been told that many of the new 2014 TV's will output a 5.1 signal (both HDMI and optical). For example, in checking the specs for the new Sony W800B it says, "5.1 Channel Audio Out : Yes." If this is true, will this change your answer in the future?

Thanks again for your help.
HDMI Guy likes this.
DrGregC is offline  
post #4 of 10 Old 02-10-2014, 05:35 AM
 
ttlnb's Avatar
 
Join Date: Aug 2004
Posts: 433
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 47
Yes, you are correct. I know most of Sony TVs will output 5.1 but it doesn't change my answer because to use ARC you have to enable CEC and that is where the fun begins;-) Also, even though the sound improvement is minimal you still get lossless sound by going to the sound bar first if it is capable of lossless multichannel PCM or has decoders for the lossless formats.

I would recommend ARC in certain situations like the sound bar only has one HDMI input but CEC will rear its ugly head. In fact in this situation if the sound bar had an optical input I still wouldn't enable ARC and use the optical connection. It is curious that there are quite a few sound bars with no HDMI connection and only optical. I think they don't want to deal with HDMI problems and tech support for it and I don't blame them. If you could enable ARC without CEC it would have more usefulness or have the manufacturers agree on a CEC standard. But, I don't see that happening.
HDMI Guy likes this.
ttlnb is offline  
post #5 of 10 Old 02-15-2014, 07:29 PM - Thread Starter
Member
 
DrGregC's Avatar
 
Join Date: Jan 2006
Posts: 87
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Liked: 12
I've returned to my weekend project...

I contacted Samsung to find a way to identify which of their TV's output a true 5.1 signal through their fiber optic (or ARC HDMI) outputs. The Samsung consultant told me that "all the Smart 2013 TV will, compatible with the DTS Premium Sound 5.1" meet this requirement.

Since I haven't yet purchased a soundbar, does this mean I could just run a fiber optic output from one of these TV's to a soundbar (that doesn't have HDMI connections) and get 5.1? Would this allow me to avoid the whole ARC HDMI question?
DrGregC is offline  
post #6 of 10 Old 02-16-2014, 06:39 AM
 
ttlnb's Avatar
 
Join Date: Aug 2004
Posts: 433
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 47
Yes you could run just an optical and get 5.1 if the TV outputs it. It does avoid ARC and CEC and a good solution IMHO. I am sure that's the reason many sound bars only have optical inputs and no HDMI.
ttlnb is offline  
post #7 of 10 Old 02-16-2014, 06:47 AM
AVS Special Member
 
primetimeguy's Avatar
 
Join Date: Sep 2005
Location: St. Paul, MN
Posts: 3,844
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 144 Post(s)
Liked: 145
Most tvs will pass 5.1 but only if from its internal tuner or apps. If you connect a Blu-ray player to the TV via hdmi and them optical out from TV to sound bar most tvs only pass 2 channel. What these means is most tvs do not pass through 5.1 from other devices. That is why it is better to pass everything through soundbar first if you can.
primetimeguy is online now  
post #8 of 10 Old 02-16-2014, 07:28 AM
 
ttlnb's Avatar
 
Join Date: Aug 2004
Posts: 433
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Liked: 47
It is TV dependent but most of the Sony TVs do pass 5.1 out of the optical. It looked like you were considering a Sony. I have had some LGs pass it but not all. The Samsung I tried didn't. Here are some the CNET tested.
http://reviews.cnet.com/8301-33199_7-57615451-221/20-tvs-tested-which-sets-can-pass-surround-sound-to-a-sound-bar/
ttlnb is offline  
post #9 of 10 Old 02-24-2014, 02:15 PM
Member
 
orijonl's Avatar
 
Join Date: Jul 2003
Location: Ashland, KY
Posts: 122
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11
What if you ran the hdmi through a switch before the soundbar and then connected the output of the soundbar to the tv? You would have to use the switch instead of the tv as the switching device, but wouldn't that be a better option?
orijonl is offline  
post #10 of 10 Old 02-24-2014, 07:34 PM
Newbie
 
mattleegee's Avatar
 
Join Date: Feb 2014
Posts: 13
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 11

This ARC stuff confused me also but i just picked up my Harmen Kardon soundbar with two HDMI in and one HDMI to TV

 

I ended up plugging the HDMI TV one to my ARC HDMI on back of TV

THen my compents into the TV as well, i skipped out on plugging my PS3 and PS4 into Soundbard and just plugged into TV HDMI ports

 

Seems fine, scary loud and 10" sub hits hard

mattleegee is offline  
Reply Soundbars

Tags
Sony



Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off