Digital Cable Box - Digital Audio Out for HD programming

[blockzilla]

Hello, I have a question about digital audio being broadcast along with certain HD programming. I have the full HD package with Time Warner cable and have no problems with HD video content, but I can't get the 6 channel sound for the audio portion. The configuration I have currently is:

Digital Cable Box: HDMI Out directly to TV. L and R audio cables to Cable/Sat L and R inputs at the Reciever (which work in sending basic audio to my system), then I also have a digital audio cable from the "Digital Audio Out" at the cable box to the "Digital Audio Input #2" at my reciever. Is this audio included in some HD broadcasts, and if so should I be getting it with this setup?

The reference point I used was that I have my DVD player L and R outs connected to the reciever L and R inputs, along with "digital audio out" connected to "digital audio input #1" at my reciever, which works great.

I assumed it would work the same for my digital cable box (a Scientific Atlanta HD DVR). Am I correct that shows like "Lost" and movies on HDHBO should be coming in digital sound? Can anyone help me troubleshoot? Thanks alot, Jim

 

[blockzilla]

Forgot to add that when I go into the cable box settings, there are 3 choices for audio output mode:

HDMI
Digital Audio Out
2 Channel

So I select Digital Audio Out and I don't get any sound from the speakers. The inputs on the receiver are labeled Digital Input #1 and #2 (instead of the analog inputs L and R for DVD, CD, Cable/Sat, etc so I don't know how to select between the 2 digital audio inputs I have connected), should the sound play automatically? My DVD digital audio automatically comes through when I select DVD on the reciever. Not sure how that works? Thanks,

Jim

 

[Buckle-meister]

It sounds like you may have to 'assign' the second digital audio jack to the input of your choice. You can easily check this by selecting each input on your receiver in turn. If you get the sound from your cable box from any one of them, then that happens to be the input your receiver has currently assigned that jack to.

Your receiver's manual will describe how to assign a jack to an input.

 

[zumbo]

I don't think you need the analog L & R cables at all. I believe most receivers give priority to the analog connection. Not sure. So, only use the digital audio out from cable box to the receiver(not analog L & R). Keep the HDMI connected as it is. I would also only use the digital audio out from the dvd player as well(not analog L & R).

 

[Buckle-meister]

Zumbo, I think you meant priority to the digital jacks didn't you?

 

[zumbo]

That is why I said "not sure". They are not needed anyway. Correct? I looked in my manual and can only find that mine gives priority to the Coaxial when both Coaxial and Optical are connected. Can't find anything between analog and digital. Still looking.

 

[Buckle-meister]

It almost certainly will give priority in the following order (best first):

1. i-link (or equivalent)

2. coaxial digital

3. optical digital

4. analogue

In terms of video, the priority in a similar order will be:

1. HDMI

2. component

3. s-video

4. composite

As for the RCA's from the cable-box; no, they are not required in this instance as a coaxial digital is also being used.

 

[blockzilla]

Thanks for the suggestions! I will do this when I get home from work tonight and post again with the results. So the digital audio cable alone will give me sound for digital HD broadcasts and also analog, like while watching non-HD broadcasts? Thanks again.

 

[Buckle-meister]

So the digital audio cable alone will give me sound for digital HD broadcasts and also analog, like while watching non-HD broadcasts?

As far as I know, yes (remember, High Definition refers to the picture, not the audio), but don't quote me on it as I don't have cable myself and only know the basics of how it works. After re-reading your initial posts, I'm fairly sure you just need to assign the second digital jack to the input of your choice. Also ensure that your cable-box is set to output Digital Audio Out as you suspected.

What receiver do you have?

 

[MDS]

The digital audio cable will not give you audio when the broadcast is analog. If your cable system has some channels with digital audio and some with analog audio, as mine does, then you also need to hookup the analog cables. The receiver's 'auto' setting will take care of choosing the correct output.

 

[Buckle-meister]

Ahh! Thank you for the correction MDS.

 

[Buckle-meister]

The digital audio cable will not give you audio when the broadcast is analog.

But given that Blockzilla can make the following choices with his cable-box:

HDMI
Digital Audio Out
2 Channel

How can he obtain both digital and analogue audio without having to go into the cable-box's menu and change the setting (from Digital Audio Out to 2 Channel) repeatedly each time the audio format of a broadcast changes?

 

[MDS]

My SciAtlanta box is HD but it doesn't have HDMI out, so my menu choices are slightly different, but here's what I think those settings will do:

HDMI out - The HDMI cable will be used for digital audio.
Digital out - The coax digital out will be used for digital audio.
2 channel - Digital signals will be decoded, downmixed to 2 channel if necessary, then output as PCM over the coax digital out.

On mine (Explorer 3100HD) the menu choice is Audio-Digital Out and the options are Dolby Digital and Other. I leave it set to Dolby Digital and that setting also works if the channel is broadcasting PCM. From experimentation, I know that setting it to Other causes it to decode, downmix, and ouput PCM if the input signal is DD and that is why I assume Blockzilla's would be similar.

The Analog outs are ALWAYS active on mine. I have both analog cables and digital coax connected from the box to the receiver and the receiver automatically chooses the right output.