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I noticed recently that PBS Buffalo was sending out a DD5.1 signal 100% of the time. Since not all programmes are DD5.1, this means that many of the programmes are sent "improperly encoded" which means that the dialogue comes out the LF & RF. Edit, this may have now changed.

I sent an e-mail to the engineer there and the fellow was again kind enough to call me (we spoke last year when they were having all the ghosting issues, which have been resolved as best they can).

Apparently, PBS Central sends out AC3 instead of Dolby E and AC3 cannot be "handled" properly by affiliates (it's apparently designed for home use mainly). Therefore, instead of sending customers only DD2.0, they have switched to DD5.1, so that at least the programmes that are DD5.1 will get to us that way. This was a conscious decision by PBS Buffalo.

People who wish to properly decode the signal to DPL will either need to use analogue connections from their STB or switch the audio output to PCM on the STB instead of DD (if available). (I simply leave it at DD)


We went on to discuss other stations. I had mentioned that National Geographic sends DD5.1 all the time too, but that they have it properly encoded. He stated that they may be using an "upmixer" available from Dolby. It works very well! PBS Buffalo may consider this device, but as you know, PBS is very funding limited.


We then discussed "tagging" of DD5.1 programming, like CBC did, but now sends out DD5.1 full time (improperly encoded like PBS when only 2 channels are present) See the following FAQ:

http://www.digitalhome.ca/forum/showthread.php?t=17870


Finally we discussed the issues that City have with DD5.1 switching and the fact that they're sending DD2.0 only to avoid the "pops" that come from their equipment - still not fixed, so still only DD2.0 from City

It's wonderful to deal with the people in the industry who care.
 

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Nice work 57, good to see that you have their ear, so to speak.
While you are at it, see if CTV as ever heard of an LFE channel . LOL
I say this, because for some reason (on BEV HD), the series Lost which CTV simsubs is coming through only as DD5.0 the .1 LFE sub is not available. I know this for sure, because my receiver tells me exactly what is coming in! It does not really matter to me , since I watch the ABC direct feed at 10 Pm, but it still frustrates me how these people can get away with such incompetence.
I don't know if this is only a BEV isue or if it is a CTV one! Sorry for the rant just thought I would share.

Paul
 

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That's a very interesting read. I'm glad to know some people actually do care about these sorts of issues and really make the effort to find solutions to them.

I face a similar problem with CBS HD (Buffalo and Seattle) but only for one show it seems, The Young and the Restless. They seem to force it as DD 5.1 yet there's only audio for LF and RF. I'm not sure why they do it this way since CBS doesn't force other shows to do the same from what I'm aware. It's just annoying for a 99% mainly dialogue show to not be able to have dialogue coming from the centre speaker, and it also causes a problem when the volume fluctuates often between soft-spoken and screaming (as daytime dramas tend to do) and having that come from 2 speakers as opposed to 1, but I digress. Just an annoyance really but can live with it.
 

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Same happens for NBC Seattle. NBC Buffalo is not yet DD5.1, so I always record Seattle, but Jay Leno is not DD5.1 and they leave their signal as DD5.1 anyway.

It's weird that he hasn't gone DD5.1 since he was one of the first to go HD.
 

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If my family is any indication, most people don't know, realize, nor care about improper 5.1.

I'm deaf in one ear which makes detecting direction of sound impossible. Thus, I can't tell improper 5.1 from my viewing position.

The A button on my receiver got pressed by someone which means my front L&R speakers were turned off.

Yet, no-one in my family noticed a difference in the sound!

I noticed three cbc hockey games in a row that the commercials (even though I FF them) didn't have any sound - every cbc hockey flaw usually gets discussed here and I thought it was odd no-one mentioned this.

The Sopranos theme song was mute - I'm thinking there was something special about this episode.

A PBS recording was mute. Ok, now I'm thinking something is definately wrong with my HT.

I changed the sound setting on my receiver to 7 channel stereo and now there was sound. I have to press my ear up to every speaker to see which ones aren't working which points me to the A button being disabled.
 

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I'm reviving this old thread since I believe I'm hearing evidence of the use of an "upmixer", mentioned in post 1 on various channels - CTV & Discovery (Bell?).

I watch the start of the CTV news at 11PM most nights. At the start of the programme, the dialogue comes out the LF & RF speakers for a short period of time, then the dialogue comes out the centre speaker properly after a few seconds. The same holds true for my daily recordings of Daily Planet.

Is this an indication of the use of an "upmixer" and are the original programmes not proper DD5.1, or is something else happening as the channels switch to these programmes?
 

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57, does the A/V DD5.1 display change or is it solid during this transition?

Could there be a delay of switching an original 2 source that had been upped to DD5.1 (putting L and R separately leaving a center "hole") then a true DD5.1 switches in or could it be that 2 channel fed to DD5.1 then is switched to PCM or something similar and is converted to Dolby Pro logic and then pumped out as DD5.1 which would then give a more or less accurate (depending on the Dolby Pro logic conversion) similar audio rendering?

The problem diagnosing problems like this is that so much "traffic" on networks goes through a central "control centre" and so much switching goes on that sometimes various decoders don't follow the switching, or different brands of encoders and their attendant codecs can confuse decoding, or not even be to spec, or be just out of spec. And even keeping equipment updated is a problem as some stuff isn't easily updated.

Tonnes of variables for sure... And this not even takes into account the BDU and their signal handling...

Cameron
 

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I mentioned it in the Extant thread, but I am definitely noticing an issue with several channels and their handling of 5.1 audio. Global Calgary is probably the worst offender, since dialog is often lost in the mix even though I've set my Optik TV box to output Dolby Digital 5.1. My AVR indicates it's receiving such a signal, but the aforementioned dialog issues and very little surround sound makes me think the signal is getting messed up somewhere along the way.

City TV is also not the best, but watching Scorpion was definitely more tolerable than Chicago Fire was (the latter is on Global).
 

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57, does the A/V DD5.1 display change or is it solid during this transition?
Sorry, I should have clarified that the signal is solid DD5.1 for the previous programme and for the "new" programme (in the case of CTV news). There is no PCM on my end. In the case of Daily Planet, this is a recording, but again, it's solid DD5.1, only the dialogue starts LF/RF, then "fades" to the proper centre channel dialogue. The transition takes a few seconds.
 

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In general the handling of audio is very poor on most channels.....great picture but lousy sound. At times it becomes so garbled with voices blending in and out that is removes the enjoyment of watching a program. But wait the commercials come through strong and clear.
 

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The PCM is not at the consumer end, but rather could be anywhere in the broadcast chain before final conversion back to DD5.1.

Central processing of multiple video sources will only add to this problem.

Cameron
 

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I'm not sure if any TV is produced as PCM. I've only ever heard of AC3, Dolby E & various forms of DD, etc. The only "PCM" I know is the conversion by the consumer STB for some equipment that may not be able to handle a DD signal and is often called "other" on STBs. That (STB output) PCM is a far cry from the uncompressed PCM utilized for CDs or LPCM on BDs.
 

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Watching regular tv and listening is pretty sad in my opinion. Improper audio and no real 5.1 most of the time. I fired up a recent movie on Netflix the other days and stuff was flying by me on both sides and to the rear just as it should. I have not noticed that on any networks. It was very much more impressive.
 

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Had to laugh at CTV completely botching the audio for their preview of next week's Castle episode. No dialog whatsoever!
 

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^^^^ Either they lopped off the centre feed of DD5.1 or a DD2.1 feed was out of phase.... That would cancel the centre channel...

Cameron
 
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