Volume unequalized on 622

[highdefjeff]

Cparker, about your volume/Dolby connection you were sniffin' at,

Volume changes when you select the different Dolby choices or when a receiver auto detects change. This is because Dolby is recorded with variable dialog level. And, according to this link:

DTV Audio: Understanding Dialnorm

[FONT=verdana, arial, sans serif][SIZE=-1]It states:

"Dolby had two choices to insure consistent loudness with their system. One would be to define a fixed digital dialog level and the means for it's measurement. If Dolby had taken this approach, dialnorm would not be needed."

and

[/SIZE][/FONT][FONT=verdana, arial, sans serif][SIZE=-1]"Instead, Dolby recognized the difficulty in achieving consensus on a fixed dialog level and made it variable within a range from -31 dBFS to -1 dBFS"

I hope this helps people to understand the differing volumes related to Dolby settings.


[/SIZE][/FONT]

 

[whatchel1]

Relates to ATSC OTA only

The article HDJeff is referring to only applies to ATSC OTA. Not MPEG 4 Satellite transmission.

 

[johnwadams]

Stupid question but, do the DirecTV HD rcvrs have this same problem?

 

[highdefjeff]

The article HDJeff is referring to only applies to ATSC OTA. Not MPEG 4 Satellite transmission.

Then Dolby must be wrong when they say:

"Dolby Digital DTV and HDTV Transmission

Television viewers are ready for the heightened excitement, realism, and quality of DTV audio with Dolby® Digital. Also known as AC-3, Dolby Digital delivers up to 5.1 discrete channels of surround sound and is applied to the final broadcast transmission signal, just prior to multiplexing with the digital video. It is used extensively today on digital satellite (DBS), cable, and DTV and HDTV terrestrial services (including ATSC and DVB)."

http://www.dolby.com/professional/pro_audio_engineering/solutions_digitaltv.html

 

[whatchel1]

Different article

Then Dolby must be wrong when they say:

"Dolby Digital DTV and HDTV Transmission

Television viewers are ready for the heightened excitement, realism, and quality of DTV audio with Dolby® Digital. Also known as AC-3, Dolby Digital delivers up to 5.1 discrete channels of surround sound and is applied to the final broadcast transmission signal, just prior to multiplexing with the digital video. It is used extensively today on digital satellite (DBS), cable, and DTV and HDTV terrestrial services (including ATSC and DVB)."

Dolby - Broadcast - Dolby Digital for DTV & HDTV Transmission

That is a different article you are now bringing up. Just because they both refer to DD doesn't mean that they related. The Dialnorm that is spoken about for DD is setup by the company that makes the product. Neither the TV station, E*, or someone at home has access to change any of what has been encoded into the original product. Just because it is used extensively in both the industries doesn't mean that we can change anything. It was encoded at the editing source and will stay that way as it is played back.
In fact read the stuff you have submitted to start with:
Why Dialnorm Implementation is Difficult

1 - Measurement tools are scarce.
Broadcast stations typically have more than one hundred VU and PPM meters, but no Leq(A) meter suitable for measuring dialnorm.

* Dolby LM100 Broadcast Loudness Meter
* Waves PAZ Protools Plugin with Leq(A) settings
* RTW Surround Monitor

2 - Measuring dialnorm is subjective.
Proper dialnorm measurement requires choosing a suitable portion of dialog within the program. It leaves the setting for music programs up to the discretion of the operator.

3 - Setting dialnorm Requires a controlled listening environment.
For music shows, Dolby advises "When setting the [dialnorm] parameter for such content, it is useful to compare the program to the level of other programs. The goal is to allow the consumer to switch to your program without having to adjust the volume control." Such careful adjustments are only possible in a controlled environment without distractions- a rare situation in broadcast stations.

4 - Measuring dialnorm is expensive.
The measurements described above require a skilled operator with the time to perform a complete level assessment of every show. While conceivable in the film industry, this concept is beyond consideration in a broadcast environment.

5 - Dialnorm requires a metadata system.
Once the dialnorm parameter has been established for a given program, it must pass intact to all destination decoders. This is simple when mastering a DVD. But it is maddeningly complex within a typical broadcast station. Many of the thousands of tape machines, servers and switchers in use at broadcast stations are incompatible with available metadata systems. Where they are compatible, implementation of a metadata system demands a major investment in interface equipment and requires complex operational procedures.

In fact most TV stations have nothing that can adjust any of this. The reason is we can't touch the encoding coming from the networks. It has been set an is just passed thru as is. The encoding is is done at the source and decoding is done in the home receiver.

 

[highdefjeff]

That is a different article you are now bringing up. (I just like to provide Just because they both refer to DD doesn't mean that they related. The Dialnorm that is spoken about for DD is setup by the company that makes the product. Neither the TV station, E*, or someone at home has access to change any of what has been encoded into the original product. Just because it is used extensively in both the industries doesn't mean that we can change anything. It was encoded at the editing source and will stay that way as it is played back.

Is that your stated opinion? You see one thing and ignore another. Was it this article that you are referring to then?

Managing DTV LOUDNESS with dialnorm

Because they say:

"the ATSC digital television system transmits metadata or data about the data to control loudness and other parameters more effectively. Dialog level, or dialnorm, is the metadata parameter that sets the loudness of all ATSC audio at the receiver. (See Figure 1 .) The content provider or DTV station sets dialnorm at the origin"

and,

"Unfortunately, due to a lack of awareness or understanding, not all DTV stations use dialnorm effectively."

AND

"Setting dialnorm properly is an easy, straightforward process for a DTV station engineer."

FURTHERMORE:

"Conclusion

In a new DTV world, putting in the time and effort to understand the process and to implement an effective dialnorm plan simply makes sense. When done properly and universally, everyone benefits from the sonic experience this system is capable of providing. Supplying anything less is simply a disservice to a broadcaster's audience."

What type of service are you providing your customers with???

 

[highdefjeff]

That is a different article you are now bringing up. Just because they both refer to DD doesn't mean that they related. The Dialnorm that is spoken about for DD is setup by the company that makes the product. Neither the TV station, E*, or someone at home has access to change any of what has been encoded into the original product. Just because it is used extensively in both the industries doesn't mean that we can change anything. It was encoded at the editing source and will stay that way as it is played back.
In fact read the stuff you have submitted to start with:
Why Dialnorm Implementation is Difficult

1 - Measurement tools are scarce.
Broadcast stations typically have more than one hundred VU and PPM meters, but no Leq(A) meter suitable for measuring dialnorm.

* Dolby LM100 Broadcast Loudness Meter
* Waves PAZ Protools Plugin with Leq(A) settings
* RTW Surround Monitor

2 - Measuring dialnorm is subjective.
Proper dialnorm measurement requires choosing a suitable portion of dialog within the program. It leaves the setting for music programs up to the discretion of the operator.

3 - Setting dialnorm Requires a controlled listening environment.
For music shows, Dolby advises "When setting the [dialnorm] parameter for such content, it is useful to compare the program to the level of other programs. The goal is to allow the consumer to switch to your program without having to adjust the volume control." Such careful adjustments are only possible in a controlled environment without distractions- a rare situation in broadcast stations.

4 - Measuring dialnorm is expensive.
The measurements described above require a skilled operator with the time to perform a complete level assessment of every show. While conceivable in the film industry, this concept is beyond consideration in a broadcast environment.

5 - Dialnorm requires a metadata system.
Once the dialnorm parameter has been established for a given program, it must pass intact to all destination decoders. This is simple when mastering a DVD. But it is maddeningly complex within a typical broadcast station. Many of the thousands of tape machines, servers and switchers in use at broadcast stations are incompatible with available metadata systems. Where they are compatible, implementation of a metadata system demands a major investment in interface equipment and requires complex operational procedures.

In fact most TV stations have nothing that can adjust any of this. The reason is we can't touch the encoding coming from the networks. It has been set an is just passed thru as is. The encoding is is done at the source and decoding is done in the home receiver.

O.k., I'll quote from that one.

[FONT=verdana, arial, sans serif][SIZE=-1]"The vast majority of DTV stations have implemented "fixed" dialnorm without knowing it, and may be using the wrong value. They do so by turning on their new DTV encoder and leaving set the manufacturer default. Or they changed the value without realizing the implication."
[/SIZE][/FONT]


[FONT=verdana, arial, sans serif][SIZE=-1]AND,[/SIZE][/FONT]
[FONT=verdana, arial, sans serif][SIZE=-1]
[/SIZE][/FONT]
[FONT=verdana, arial, sans serif][SIZE=-1] "At minimum, stations should borrow a dialnorm measurement tool and set their DTV encoder dialnorm parameter to the average measured value at the encoder input."


[/SIZE][/FONT]

 

[tempVAdish]

Are we allowed to stir the pot, or is that a no-no? I could really make a funny joke here about all this, well, funny to me

 

[highdefjeff]

Are we allowed to stir the pot, or is that a no-no? I could really make a funny joke here about all this, well, funny to me

Stir away! I'm laughing a bit myself. I am not here for entertainment, but I am well aware that these exchanges are sadly, just entertainment for some. Shoot, I can take it!

 

[whatchel1]

3 - Setting dialnorm Requires a controlled listening environment.
Such careful adjustments are only possible in a controlled environment without distractions- a rare situation in broadcast stations.

 

[sam_gordon]

In fact most TV stations have nothing that can adjust any of this. The reason is we can't touch the encoding coming from the networks. It has been set an is just passed thru as is. The encoding is is done at the source and decoding is done in the home receiver.

I hate to agree with Jeff, but there ARE devices available to the broadcaster that can adjust the dialnorm. The Dolby DP-569 will take the unencoded surround audio and encode it using the dialnorm you program into it. Or it can accept metadata (from the network) for the established dialnorm.

Neural audio also makes a box (Multimerge+NLC) that can take the discrete unencoded audio (stereo OR 5.1), "even out" the drastic changes, and send the discrete 5.1 on to the DP-569 (it will also "make" 5.1 from a stereo source).

Now, I know networks don't want the local broadcasters "changing" the audio signal (dialnorm or otherwise), but using these two devices in conjunction can really cut down on the drastic audio changes between commercials and programming.

ETA: I don't know how a broadcaster can just pass the encoded audio from network onto THEIR encoder. That would mean you'd have two different TYPES of audio... encoded DD5.1 from network and unencoded discrete for local content. Will a broadcasters encoder switch between the two?

 

[whatchel1]

ETA: I don't know how a broadcaster can just pass the encoded audio from network onto THEIR encoder. That would mean you'd have two different TYPES of audio... encoded DD5.1 from network and unencoded discrete for local content. Will a broadcasters encoder switch between the two?

Yes, we have Lietch device that switches between the 2 sources to route to the OTA encoder. In this case a Harris Flexi-coder we are hoping to replace it with the new Harris Net VX. NBC in our case controls all the encoding of the DD 5.1 which goes directly into the Flexi-coder. When I worked at our sister station a CBS facility; CBS had the same control. PBS also sends out their encoding embedded in the stream as well but that was 4 yrs ago when I worked at a PBS station so can't say for sure if it is the same now but most likely. I can't speak for ABC & FOX have never worked for them. Thing is to do the adjustment that is being talked about it would mean the audio would have to be broken out of the chain then reinserted it is possible but would mean one has to run in a delay. That also means that it will take timing devices to re-time the video & audio for re-insertion into the stream. That can be done but gets tricky. That is why most facilities just pass it on. Also that is what is talked about as needing a controlled environment which is rare in a broadcast facility. Even less possible in the case of E* or D* where they are monitoring hundreds of incoming signals then refeeding them to the uplink.

 

[sam_gordon]

What's the model number of that Leitch box you're using to switch between a source w/encoded audio and an source with unencoded audio? I'm familiar with both the Flexicoder & NBC audio. NBC also sends discrete 5.1 audio embedded with the video. The Flexicoder has an adjustment to delay the video to match the audio. Also, that delay doesn't need to be exact, just close enough:up.

Are you a fully HD plant? Or are you upconverting your studio feed?

 

[whatchel1]

Sorry misstated

What's the model number of that Leitch box you're using to switch between a source w/encoded audio and an source with unencoded audio? I'm familiar with both the Flexicoder & NBC audio. NBC also sends discrete 5.1 audio embedded with the video. The Flexicoder has an adjustment to delay the video to match the audio. Also, that delay doesn't need to be exact, just close enough:up.

Are you a fully HD plant? Or are you upconverting your studio feed?

Sorry I misstated the Lietch is our encoder to the Flexi for our plant(at the moment can remember the model #). The Flexi does the switch between NBC & our station. The embedded 5.1 is what is sent out for our station during HD programming. My CE had to recently tweak the audio a bit to get the lip sync corrected and adjust our SD volume to close to NBC's volume. I did the monitoring of the signal since I have the only digital return in the building. I'm supplying my old VOOM receiver at work on the old analog monitor that is in my office. After the recent change out to the new sat receivers & NBC's changing of audio channels. I do make mistakes and admit to it when I do.