Digital Cable Hookup (1 Viewer)

[WilliamHg]

Hi Guys, Just got digital cable a few days ago and so far it sounds great. Question is this: I'm only running the coax cable from the wall to the digital box and from the box to my TV. That's it. The box does have an S Video jack and audio jacks but I'm not using them. My S Video is running from my DVD player to my TV and the optical cable is running from the DVD player to my receiver. TV and DVD player are running to my receiver also. VERY simple setup but was wondering if I might be doing something wrong or maybe hurting something by not using the audio jacks on the digial box. I did try using the audio jacks on the digital box but the sound was degraded compared to how it's setup now. Thanks. William

 

[Rick_Brown]

Does your cable box also have a digital or optical output? If so, this should be connected to your receiver. You will then be able to hear Dolby Digital when broadcast. My cable provider broadcasts 5.1 DD for many movies.

 

[WilliamHg]

Thanks Rick. My receiver has 1 optical and 1 coax digital jack. The optical is running to my DVD. It wouldn't hurt anything to run coax from the other digiatal jack? Just thought they might both have to be the same but wasn't sure. I did have it connected but didn't notice any difference but that may be because nothing was playing in 5.1 at the time. I'll try again. William

 

[Nick A. G.]

What make/model is your receiver? The digital coax input on it could be a separate input. But on basic receivers, it's possible that it shares the same input as the optical, meaning that you can only use one or the other.

In either case, at least run the analog audio cables from the box to the receiver. That'll improve your sound dramatically. Second, if your box has a digital output for audio (my Scientific Atlanta Explorer 2100 does), UTITILIZE IT. Several movies on premium channels are broadcasted in 5.1 surround. If your TV has a second s-video input, run that as well. You'll enjoy a sharper picture that way.

 

[TimTurtino]

This is pretty unrelated, but on my digital cable box (I had to beg the S-video version from Comcast-- it's a Magnavox DCT-2224) I have the most incredibly difficult time telling the difference between S-vid, composite, and cable box. For reference, I can usually tell the difference between better and worse cables of a given variety. This is true whether I'm watching analog or digital channels.
My guess is that this means that either the comb filter on my TV (Panny CT-27SF35W, 3D comb filter) is awesome, or the comb filter (or equivalent??) in the digital cable box isn't really up to snuff. Does anybody know anything more about this?
This probably belongs in a forum more dedicated to cable boxes, but unfortunately, I don't know where those are. :frowning:
Me

 

[WilliamHg]

Thanks guys. My receiver is a Sony 740. The digital box has a digital audio out jack and my receiver has 1 optical and 1 coax digital jack. When playing a DVD that's in 5.1 it will show up on the front panel on the receiver but nothing changes on the display for movies on TV so far. It might just be that I can only use one of those jacks on the receiver as Nick mentioned. Anyway back to my original question, do you guys think I have everything setup up ok other than possibily the digital hookup? Thanks, William

 

[Rick_Brown]

William, when you say "TV and DVD player are running to my receiver also" I take this to mean that you are running audio out from your TV to the receiver? If so, I agree with Nick that you should run cables directly from the analog out of your cable box into your receiver. This way you are bypassing the preamp/amp audio section of your TV on the way to your receiver. Should give better sound.

 

[WilliamHg]

Well I pulled the cables out of the TV and ran them from the digital box to the audio IN on the receiver but I have to cut the volume up almost half way before I start getting sound. The other way I would start getting sound almost immediately. If I don't bypass the TVs pre amp what will happen to the TV? Any problems down the road that might come up? William

 

[WilliamHg]

Well,I'm going to call Comcast now and look into it again. I don't really think they know much but will try again. You'd think connecting to the digital box would make a difference but to be honest it sounds terrible. I'll take it back if that's what I have to do but I can't really listen to it like that. Of course I could have it connected wrong but it IS connected the way I said it was. Waiting for your replies fellas. Thanks, William

 

[GregLee]

Suggestions (amplifying those already made):

Connect cable box's S-Video output to TV's S-Video input (or perhaps route this signal through your receiver). This will improve the picture for some digital cable channels by removing the graininess caused by interference between video and color signals. But it's possible, I suppose, that your TV's comb filter is so good that there will be no improvement. The S-Video connection avoids a comb filter altogether.

Connect the cable box's digital audio output to the corresponding input on the receiver. For those cable channels that have a digital audio signal (not all do), you'll get slightly wider frequency response for the Dolby Digital 1 or 2 channel signals and, as Rick said, much nicer 5.1 channel sound for a few movies on premium channels. For this to work right, you'll probably have to set up the receiver by (1) assigning the coaxial digital input to the appropriate device, (2) asking it to use digital rather than analog input mode, (3) turning on Dolby processing for this input.

 

[WilliamHg]

Thanks Greg. The only difference I've noticed so far is that I have to turn the volume up more to get to the same listening level which is alittle more than half way. Volume runs from 1 to 65 and I have to put it on around 40 to 50 depending on the station. When running from TV to receiver I only need to turn the volume to about 30 to 40 at the most. It doesn't bother me but just am wondering why that is? Thanks. William

 

[GregLee]

Digital mode should sound better, and I'm sorry that you're not hearing an improvement. I don't what could be wrong. Do you subscribe to any premium channels so you can look for a movie in 5.1 sound to test whether that is working?

On the loudness difference, I guess there is no particular reason why the TV's and the cable box's sound outputs need to be at the same level. Possibly you can adjust one or the other.

 

[WilliamHg]

Thanks Greg. I talked with someone at Sony and she said it's probably because the receiver has more power than the digital box. I'm ok with that. She also said as far as my DVD player goes that since I have a digital optical cable running from it to my receiver that I don't need to connect the audio cables from the DVD player to the receiver because the optical cable will handle all of it. I'm wondering if I play a DVD that's not digital whether it will play or not, like a DVD that's Pro Logic. Haven't tried it yet but will tonight. Will an optical cable handle ALL audio? Digital or Analog? William

 

[WilliamHg]

Forgot to say I don't have any premium channels yet. Just basic digital and the basic movies that are on it like Action, Encore, etc. I read on another post that the optical cable WILL handle more than just digital sound so that answers my question. Thanks for your help Greg. William

 

[GregLee]

Action and Encore do have some movies with 5.1 sound.

 

[Rick_Brown]

"When running from TV to receiver I only need to turn the volume to about 30 to 40 at the most. It doesn't bother me but just am wondering why that is?"

William, these reason for this is that your TV is amplifying the signal prior to it going to your receiver. The cable provides a line-out signal, your TV is boosting this and then your receiver is boosting it again. Louder, yes, but this usually degrades the sound as the TV in the amp is likely much lower in quality than your receiver's amp.

 

[WilliamHg]

I've noticed that too but found a workaround. I cut back on the master volume which is my TV remote just a little bit then use the receivers remote to control the volume. It works pretty well. If I don't do that then it is VERY scratchy sounding. Thanks Rick. William