How to get Digital sound from cable box (1 Viewer)

[Mark Dill]

Hey, got a basic question here. Out of my cable box, I use component cables for video and the audio is hooked up with normal red-and-white composite cables. I see icons on my HD channels indicating that a program is in DD5.1 sound, but how am I going to hear it if I only have it hooked to the TV through composite? I don't think I can, right? I think I need to hook up an optical cable from my cable box to my receiver, or I can trade in my box for one with an HDMI out. (those have a 6 month waiting list, apparently)

I just moved in and I haven't hooked up my receiver to the TV yet, but I just want to make sure I am on the right track here. I just have the cable box connected directly to the TV, with video component cables and audio composite cables. I brought up this concern to the cable company and the rep assured me I would be able to get DD5.1 sound with the way it is hooked up now, but I don't see how that can work. Please help?

Thanks.

 

[bradhart]

either the rep didn't understand the question or the were full of crap. Your cable box is still receiving the digital signal but with only your standard left and right channels out you aren't going to hear it. You need to have either the digital coax or optical cable from you cable box to your receiver and all your speakers hooked up before you are going to hear that 5.1 surround sound.

 

[Ed Moxley]

You should be able to go into the cable box's setup menus, and choose PCM or Stereo, for audio output, and hear the programs. A lot of people have HDtv, and don't have surround setups. Once you get your A/V receiver setup again, go back into the cable box setup menus, and set the audio output to digital, or Dolby digital, and use a digital cox or optical cable from the cable box to the A/V receiver.

 

[Mark Dill]

OK, thanks for the info, guys.

 

[JohnRice]

Mark, part of the problem may be with your terminology. There is no such thing as "composite" audio cables. Composite is typically a video term and does not apply here. The red/white connections are left/right ANALOG and are not capable of discreet surround sound. Digital sound can be passed by either optical or coax (once again, not "composite", even though the cables are the same) but if your box does not have any digital (or 5.1 analog) output, you can't get discreet surround. Are you sure the box doesn't have a coax digital output? If so, that is the way to get 5.1.

 

[Jeff Gatie]

Just as an aside, the coax digital audio out is looks just like a single audio out, except it is colored orange. I you have an orange RCA out on the back of the TV, get a regular yellow ended RCA video cable and hook it up from there to a coax in on the receiver. Assign the coax in on the receiver to your cable/sat setting and see if you get digital audio.

 

[Mark Dill]

Ah, thanks, I never know what to call the basic red/white audio cables. They frequently go along with a yellow composite video cable, so I called them composite, but I see how that was misleading. Analog it is.

Unfortunately, my cable box does not have a digital coax out, so it looks like I need to use the optical port. Also unfortunately, my TV does not have an optical-in, so I need to go straight to the receiver. Not real crazy about that, since it means I have to power off receiver and TV every time. (or TV and cable box, I suppose) I normally like to have it setup so I only need to turn one device (the TV) on or off.

 

[Mark Dill]

Actually, I just checked it, and my cable box DOES have digi coax out, so that's nice, but it still doesn't solve my problem because my TV does not have digi coax in. Apparently the only way to get digital audio to go through the TV is via HDMI. Is that normal? Seems a bit odd for a brand new TV. This is a Panny 50" Plasma.

 

[Jeff Gatie]

The sound you get from digital won't be much different from the analog when going direct to the TV. Even if you send the audio through the HDMI, the TV is still going to downmix it to 2 channel, which is essentially what is being done by the cable box when it sends it via the analog.

I'd wait until you can get the receiver hooked up, then you can go digital coax and get true 5.1.

 

[Mark Dill]

Interesting, good to know, Jeff. I'm surprised that the TV would downmix it. Even if I connect from optical out on the TV to my receiver?

Direct to the receiver it is, then.

 

[JohnRice]

The TV only has 2 speakers, so it has no choice but to take a 5.1 digital audio input and mix it down to 2 channel.

so, as was already recommended, I would run the analog audio outputs from the cable box to the TV, or just use hdmi. You'll only get 2 channel out of the TV anyway. For basic TV viewing, you can just turn on the TV (and cable box) and use the speakers in the TV. When you watch movies or want full surround sound, you turn on the receiver and use the audio from it instead. You can use either optical or coax digital to get the audio from the cable box to the receiver. It really makes no difference. There are more options for hookup and I'm sure someone will come in to correct my omissions, but there is no need to point out every possible option.

 

[JohnRice]

Something just occurred to me regarding you last post. Are you sure the TV has an optical out rather than just an input?

 

[Ed Moxley]

Optical out, on tvs, are usually only used for getting 5.1 surround from the built in tuner, when watching HD cannels OTA. They're not meant for running an HDMI from the cable box to the tv, and then an optical out from tv to the receiver.

 

[Brent_S]

Mark, once you get your receiver online, don't be surprised if you still don't get DD even if the program says it's encoded. For the major network providers, you're at the mercy of your local affiliates that feed the cable provider. In my market, the CBS and NBC stations aren't 5.1 enabled while Fox/ABC/PBS are. Major bummer since a majority of the series we watch are on CBS.

-Brent