Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

iCalifornia

macrumors newbie
Original poster
Apr 16, 2012
6
0
San Francisco
Do I need to run an optical audio cable to my AVR in order to take advantage of 5.1 surround with my AppleTV? I noticed on my iTunes purchased content the center channel and two rear channels are not being utilized. Running the latest firmware, and I am able to take advantage of the extra channels using my XBox.

Also, I thought the advantage of HDMI was that only one cord was needed to handle all of the information. Any help on this would be greatly appreciated.
 

JoeBlow74

macrumors regular
Aug 2, 2012
218
9
Do I need to run an optical audio cable to my AVR in order to take advantage of 5.1 surround with my AppleTV? I noticed on my iTunes purchased content the center channel and two rear channels are not being utilized. Running the latest firmware, and I am able to take advantage of the extra channels using my XBox.

Also, I thought the advantage of HDMI was that only one cord was needed to handle all of the information. Any help on this would be greatly appreciated.



Toslink (optical) does not pass surround, only bitstream stereo. The only way you will get surround is if you use HDMI, or Digital out.
 

mic j

macrumors 68030
Mar 15, 2012
2,663
156
Toslink (optical) does not pass surround, only bitstream stereo. The only way you will get surround is if you use HDMI, or Digital out.
Incorrect. Toslink (optical) passes surround sound just fine. It will not pass HD audio, though.
 

Pyromonkey83

macrumors 6502
May 24, 2009
325
0
OP, are you downloading directly from iTunes or ripping the media yourself?

Also, are you using a true receiver or a 5.1 Home Theater in a box system?

I am not sure about this so dont actually hold me to it, but as far as I know iTunes downloads are downloaded with Stereo sound using an AAC audio codec. The stereo sound, however, is using the Dolby Pro Logic II codec system, meaning it works on both 5.1 and 2 channel systems. A receiver set up to support DPLII should be able to analyze the audio stream and interpolate the audio streams between the surround system in a pseudo-surround way.

I have no idea if a Theater-in-a-box could handle this, and it probably depends on the system you have.

If you can get me the info of your system I can help further.
 

aross99

macrumors 68000
Dec 17, 2006
1,540
1
East Lansing, MI
There is a "Dolby Digital" setting on the Settings/Audio & Video menu in the Apple TV that needs to be "on" or "Auto" in in order for the Apple TV to output 5.1. Obviously the media you are watching also needs to be in 5.1...

You should be able to use either HDMI or the Toslink optical cable...
 

iCalifornia

macrumors newbie
Original poster
Apr 16, 2012
6
0
San Francisco
OP, are you downloading directly from iTunes or ripping the media yourself?

Also, are you using a true receiver or a 5.1 Home Theater in a box system?

These are direct from iTunes purchases. My receiver is a Denon 1713 with an AppleTV third gen connected to it via HDMI.

>> I figured out the issue. The first program I tried was Mad Men season 5. For whatever reason it doesnt output 5.1—and it was the first thing I played—but everything else works fine.
 

DJRumpy

macrumors newbie
Jan 14, 2011
18
0
To output 5.1 sound from an AC3 audio track via an Apple TV, go into the Audio and Video settings, and set the Dolby Digital to 'On'. That will output a 5.1 AC3 bitstream via TOSLINK (optical) to your tuner.

If you use HDMI, you will most likely end up with downmixed stereo since AAC capable tuners seem to be a bit rare.

Note the options for the Dolby setting are 'Auto' and 'On'. It MUST be set to 'On' to get the 5.1 bitstream via optical out.

Your video file should have a 2 channel AAC track, and a disabled 5.1 AC3 soundtrack in order for it to output the AC3 track by default. MP4Tools (beta) will create this file for you just by remuxing an existing M4V video file that contains a 5.1 source audio track (the video will not be re-encoded...only the audio).
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.