Comcast HDTV & DD5.1 (1 Viewer)

[Michael Burnett]

I thought I was where I wanted to be. I've lurked for years, and finally made the investment (got the permission !). Got my Denon 3803, a full set of Boston Acoustic VR-M (VR-MC, VR-M60s, VR-M50s, PV800) speakers to go with my Mits 55857 and Toshiba 5109 (from several years ago). I'm loving life.

Then within days Comcast comes out with a deal for me to move to their HD package. Too good to deny.

I am thrilled with the sound, and the HD picture is great. (The "lower" channels leave a bit to be desired. Also, waiting for more HD content - like CBS, PBS, DiscoveryHD, ESPN-HD.)

Anyway, enough "sharing" - here's my problem. When the Comcast installer came out we had a DD5.1 signal on the cable (when transmitted). I couldn't have been happier. However, now I can't seem to get anything from the cable to be detected by the Denon as a digital (let alone a DD5.1) Everything is detected as analog. The audio runs from the Comcast box to the Denon via optical cable.

Of course, when calling Comcast they insist that my problem is with the Denon. They may be right - I could be experiencing a cockpit error. I figure the first step to determining the source of the problem would be if I could somehow "see" if Comcast's Motorola box has an indicator of the type of audio signal it thinks it's sending. Its not worth pursuing if I don't know that I've got a 5.1 signal, right?

Other ideas?

You can see I'm a semi-newbie. I could have screwed something up. I do get some unintended consequences from the interactions between my kids & the remotes.

Thanks in advance,
Michael

PS - Sorry if this is in the wrong thread. I tried all day to search for other similar problems, but couldn't use the search feature.

 

[Stu Rosen]

I have the Comcast HDTV Motorola box, and though I can't be 100% sure, I believe that the Comcast channel/show banner that pops up when you hit the channel states whether the broadcast is in 5.1.

And I think that it only shows that when it's actually receiving a 5.1 signal. The reason I think this is that I seem to recall that the 5.1 indicator wasn't there during commercials.

Hope this helps.

 

[Michael Burnett]

Stu,

Thanks for your response.

I used to think that also. However, when speaking to Comcast technical support, they said that that is just information from TVGuide. They say that the banner does indicate that the signal is 5.1 somewhere, but not necessarily that they (Comcast) is sending it as such.

If it were only that simple :frowning:

Thanks,
Michael

 

[BrianMagog]

I have read that Dolby Digital 2.0 is interpreted as Dolby Pro Logic on Denon receviers. Is it reading "Pro Logic" but "Digital", or is it just "Analog"? In my experience, most stuff through Comcast HDTV in my area is 2.0; only the rare movie is 5.1. Some sporting events have been 5.1, but the vast majority have been 2.0. It has also been my experience that the "5.1" tag means nothing.

 

[Michael Burnett]

The Denon is reading "Analog", with the PLII processing indicator on.

I know that much of the audio will be 2.0, but I would like to know that I'm "catching" the little 5.1 there is properly.

Thanks,
Michael

 

[Matt Weldy]

Did you ever try changing the digital input with your dvd player to see if the problem follows. If the dvd player now dosent work you know its the reciever. If it follows the switch you know that its the cable box. I have comcast and not every program is in 5.1 however whenever I get the 5.1 banner my reciever is getting it also. I also have the 3803.

 

[Michael Burnett]

Matt,

Thanks for the reply. Yes, the 3803 tracks changes in the audio signal from my DVD player appropriately.

Did you mean to actually change the cabling - using another optical input?

I'm inclined to think that something in the cable box is awry, but I wanted to see what the cable box "thought".

Hmmm - you say that whenever the comcast/TVGuide info indicates that the audio is DD5.1, you are getting a 5.1 signal out of the cable box? That's the performance that I want!

 

[Matt Weldy]

Yes I did mean change the input on the back of the reciever. If you have it in input three and you move it to input 4 and still have the trouble you know its the box. Or if the trouble is gone you know its the reciever. Its and easy trouble shoot. Also I should say SO FAR everytime I get the 5.1 banner I get the 5.1 sound.

 

[Chuck West]

Can you guys tell me which channels Comcast carries in HD?

 

[Matt DeVillier]

Michael,

if you only have the cable box connected to your receiver via the optical cable (ie, no analog cables), then you don't have to worry about anything. the box (a moto5100 I'm assuming) will correctly pass along whatever comcast is sending you (which is whatever they are being provided). There's nothing you need to set on the box to pass dd5.1. If this is the case, and the denon is still reporting 'analog', then that's just an idiosyncracy of the denon as I'm pretty sure the box isn't sending an analog signal via the optical output =)

 

[Larry Marq]

If the Denon detects "analog" then there must be an analog connection as well...either disconnect the RCA's or hit the auto mode switch until it reads "digital". Sumpin's hokey.

 

[Michael Burnett]

Well,

The mystery is solved. Thanks to all of your input.

After checking the cabling into the Denon (which was correct), I followed the cabling back to the cabling box. Lo and behold, the optical cable from that end was disconnected. (Anecdote: Upon realization and my expressing joy at uncovering the source of the problem, my wife asked what happened. When I explained, she responded with her story about the need to dust in between components - despite the closed-in cabinet she required. So ultimately, this was a dust[ing] related problem!)

So now, the Denon is (in "Auto" detect mode) showing "Digital" for all signals. It is showing "Dolby D" for all 5.1 signals. As Matt indicated, this happens every time that the TVGuide banner indicates that a channel is sending 5.1.

Matt, Matt and Larry thanks for the input.

Brian, the 5.1 tag seems to really indicate a complete DD5.1 audio signal.

Chuck, Comcast is now sending local ABC, local NBC, HBO, Showtime and Comcast HD (a sports channel that has very little content).

Thanks again to the HTF community for a place in which to sort this out.