I've noticed a variety of encoding schemes used on HD channels, and lately have been noticing that many channels encoded with full Dolby Digital Surround seem to be down in level by quite a bit. As I'm sure is true of many of you, I have a particular number that is my preferred movie listening level for DVD's and Blurays. With certain channels like TNT-HD I find I have to turn it up another 5-6 "numbers" on the dial, roughly say 3-4db's. I find this is only true of movies on these channels and not shows. Additionally I have noticed a bit more compression in the sound than I would expect or hope for. Is this all consistent with other peoples experience? Are the fiber based systems like FIOS offering better bit rates for audio as well as video (I've read the video is a mixed bag, some is better, some is worse, some is the same).

This should probably be a separate post, but I keep reading that Comcast is trying to become the premiere source for HD content. They always talk about HD VOD, extensive HD lineups, etc. However, Comcast took over for Insight here about 6 months ago, and I am yet to see any HD VOD, and I've only gained maybe 3 or 4 HD channels. When do you all think the HD channel lineup will finally begin to fill out and the HD VOD will cease to be vaporwear here? I'm not real keen on 6 dollar HD movie rentals, but Showtime HD on demand would be nice.

It seems like to me the things encoded in 5.1 come out at a much lower level then stereo-encoded broadcasts. I have a Sony STR-810 receiver and listen to everything through it. Tuner is S/A 8300HD DVR from Comcast. Seems to happen on most channels.

Dialnorm, which is the very parameter of Dolby Digital that was supposed to even out the dialog level between programs and channels, is for the most part incorrectly used and has actually made the situation worse. There are very few if any (I don't know of a single one) channels or networks that assign a dialnorm value to each program based on its dialog loudness and instead use a constant value. The most common is the default -27db but it can vary quite a bit especially among broadcast networks. CBS is the loudest at -31db and NBC is the softest at -23db (at least they raised it 1db from what it used to be). It gets even more complicated with some networks (like NBC) which send 2.0 material flagged as 5.1.

The audio level discrepancies have become much worse with digital transmission. With digital audio's improved dynamic range compressors should not be required, but this has also had the consequence of allowing greater discrepancies in levels between program elements - especially commercials. Add in the level differences between channels and one is required to keep a thumb on the volume control buttons.

FiOS gives you the same bitrate that they recieve from the provider, no additional compression.

...Additionally I have noticed a bit more compression in the sound than I would expect or hope for. Is this all consistent with other peoples experience?...

I have Comcast and this is EXACTLY what I'm experiencing on the NBC-HD channel. It drives me nuts and I've done everything I can think of short of cancelling Comcast to get them to correct it.

I have Comcast and this is EXACTLY what I'm experiencing on the NBC-HD channel.

Comcast is only passing on what your local station is giving them.

Audio on TV Shows is all over the road..

CBS is the loudest at -31dbJust in passing I mention that KCBS-DT here in LA finally conceded to the unending complaints they must have been receiving from viewers about the extraordinary super-loud audio on everything they presented.

It is no longer the absolute loudest channel here in LA. In fact it is now quite "normal" and listenable.

I believe (based only on comparison of my SPL numbers watching CBS vs. other local channels known to be at -27db dialnorm) that KCBS-DT must now be operating with that value as well, since it now sounds about equally loud.

And that's a good thing.

along the lines of the initial post.. why is it that some channels sound great in 5.1 ( starz, Hbo, cbs) some ok( tnt) and some just awful and compressed( USA hd, scifi hd)

Has anyone else noticed this?

Just in passing I mention that KCBS-DT here in LA finally conceded to the unending complaints they must have been receiving from viewers about the extraordinary super-loud audio on everything they presented.

It is no longer the absolute loudest channel here in LA. In fact it is now quite "normal" and listenable.I checked KCBS-DT from OTA tonight during network programming and confirmed that the dialnorm is now -27db. The CBS HD network is still -31db.

Wow thanks for all the great responses, this is helpful. At least I know I am not alone in my concern over the sound on digital channels. I still don't get USA HD or Scifi HD, but doesn't seem like I'm missing much. TNT HD I find pretty awful, so for it to be called "OK" implies to me that some must really be messing things up. I watched LOTR and UltraViolet on TNT and found the sound not only to be overly compressed, but actually distorting. At first I thought maybe it was something with my system, but after checking everything the next day, and re-watching the movies (I recorded them on my dvr), it was quite clear that this sound issue was in the movie. I'm very disappointed with my HD cable experience over the last two years, while I hoped things would improve, it seems like they have only gotten worse. Even though the resolution is higher, I don't even consider the picture better than a standard DVD most of the time, and the sound doesn't even approach that of a DVD, let alone the better HD video format sound encoding schemes.

Pardon the pun, but I think we need to make a lot of noise about this. Just as we made a lot of noise about reduced PQ with services trying to stuff too many channels into one. Get some of the tech writers to do some stories (they're always looking for topics anway). It's very annoying when I have to adjust audio on my system by as much as 10db when going between HD channels.

It's very annoying when I have to adjust audio on my system by as much as 10db when going between HD channels.

Tell me about it. Drives me nuts too.:mad:

Pardon the pun, but I think we need to make a lot of noise about this. Just as we made a lot of noise about reduced PQ with services trying to stuff too many channels into one. Get some of the tech writers to do some stories (they're always looking for topics anway). It's very annoying when I have to adjust audio on my system by as much as 10db when going between HD channels.
There's enough noise about it already. Loudness and lip sync are the two biggest problems in DTV audio. The last thing we need is a bunch of "writers" chiming in with their $0.02 on what the problem is. Next thing you know we'll have congress involved. (Ooops, too late...)

Dialnorm as already mentioned is already part of FCC regulations. Broadcasters and content producers seem to be unaware of it. We need to make them aware of it.

http://en.wikipedia.org/wiki/Dialnorm

Interesting wiki. Generally correct, but not too useful in explaining a concept to someone who may not understand the underlying idea.

The link provided to this article at the bottom of the wiki does a good job of discussing the issues. They mention it not being an issue for DVDs but I'm beginning to notice more disparity even with those as well as BluRay. Means they're hiring too many kids on the cheap to do the authoring.
http://etvcookbook.org/audio/dialnorm.html

One of our local stations, KTVU, just installed new gear and before that the switch from network programming and even local ads to the news would have you grabbing the remote as the news level would blast you out of your chair. Now the audio is equal between programming and the news program.

Dialnorm (short for dialog normalization) is a rather simple concept. The average loudness of the dialog is measured and represented as the dialnorm value. That value is used to set a volume control (attenuator) in the Dolby decoder. The louder the dialog, the lower the volume is set. This value is intended to be a constant for a given show or element (like a commercial). This way the dialog can remain more constant. The actual numerical value is the loudness with respect to the highest level that can be sent (0db) and is always a negative integer between -1db and -31db. Typical values are between -22db to -31db. The lower the dialog loudness is, the lower the dialnorm should be (larger negative number) and less attenuation will be applied in the Dolby decoder.

Of course this is easier said than done. Due in large part to limitations from lack of standards to carry the dialnorm value from production to air, the networks just use a constant value. Unfortunately they all seemed to pick different values which not only didn't fix the program-to-program problem, it made the channel-to-channel differences worse.

NBC is the softest and CBS is the loudest, although at least one of the CBS owned stations has been reported to have lowered it to the same range most use. Fox is somewhere in the middle and the ABC stations set the value themselves so it can vary.

Interesting wiki. Generally correct, but not too useful in explaining a concept to someone who may not understand the underlying idea.Seems a bit biased against CBS (although I agree that -31db is too loud) and doesn't mention NBC's soft levels which gets alot more complaints in this forum. My theory is that since CBS's audience tends to skew older, CBS makes it louder to compensate their hearing loss.

Seems a bit biased against CBS (although I agree that -31db is too loud) and doesn't mention NBC's soft levels which gets alot more complaints in this forum.

No, it was not a dig at CBS (although they are WAY too loud during football.) I was just commenting that you have to have a good understanding of the basics of DTV audio in order to understand completely what was written in the wiki. What everyone needs (including CBS) is a "DTV Audio for Dum-- uh, Video Engineers." DTV Audio isn't rocket science, but because of priorities at their stations, many broadcasters don't have the time to study the basics of what DTV audio is trying to do. They assume it is just a digital version of what they've always done, which it definitely is NOT.

My theory is that since CBS's audience tends to skew older, CBS makes it louder to compensate their hearing loss.

:D:D Maybe they need Garrett Morris to help them out with captioning, too! (SNL reference.)

:D:D Maybe they need Garrett Morris to help them out with captioning, too! (SNL reference.)Har har....

No, it was not a dig at CBS (although they are WAY too loud during football.) I was just commenting that you have to have a good understanding of the basics of DTV audio in order to understand completely what was written in the wiki.I was commenting on the wiki.

<brokenrecord>There is a variance of loudness between various programs and it's about the same on any channel, so a static dialnorm has little chance of being correct. Until there is some sort of matching of dialnorm to the program material I don't see a need for each network and channel to have a different static value and make the situation worse. IMO if everyone just used a common value (such as the default -27db) until they get their dialnorm act together it would be a step forward. The two loudness bookends are NBC and CBS. Their affiliates can override the network's metadata dialnorm and DRC on a DP569. In the case of CBS stations they will still have the 5.1/2.0 switching. Obviously complying with the original intent of dialnorm would be the best approach, not to mention staying technically legal.</brokenrecord>
http://img153.imageshack.us/img153/181/dp569override2vq8.th.jpg (http://img153.imageshack.us/my.php?image=dp569override2vq8.jpg)
:D:D Maybe they need Garrett Morris to help them out with captioning, too! (SNL reference.)I'm for that. They should try it out with Katie Couric.

Getting CBS stations to force a Dialnorm value of somewhere around -25 and also forcing a DRC profile (currently CBS sends "none") would do a world of good in making CBS play nicely with other channels. Unfortunately, O&Os are mandated to do what the Network wants (except in LA) and other affiliates don't have the inclination (or staff) to think for themselves. But again, it's much more efficient to get things set right once rather than have 200 stations guessing. It's the getting it right in the first place that has been a problem.

You gotta give NBC credit for trying and involving the affiliates in the process. Fox doesn't give their stations the ability to change their signal, but does require the station to set it for local content. ABC seems to be in the "even a broken clock is right twice a day" mode.

I agree that changing it once correctly is the most efficient approach, but it doesn't look like it will happen any time soon. Stations can change this parameter in a minute. The need for hundreds of stations changing isn't really an issue as the decision is made at the station level.

I'm not sure what NBC did when working with the stations other than encouraging them to match their lower than everyone else audio levels, which I would guess boils down to the local dialnorm matching the network. I saw where one of their O&Os had their local dialnorm set at -27db which was 5db higher than the network -22db at the time. I suspect that was not an uncommon situation. With NBC getting more complaints about audio levels than the others on this forum one could question the validity of their recommendations. I would imagine that station GMs would not be happy having their station be the softest in town especially during the local news.

When the network dialnorm begins to follow program loudness it's a simple change back to turn off the override. Compared to adding subchannels this is super simple.

Getting CBS stations to force a Dialnorm value of somewhere around -25 and also forcing a DRC profile (currently CBS sends "none") would do a world of good in making CBS play nicely with other channels. Unfortunately, O&Os are mandated to do what the Network wants (except in LA) and other affiliates don't have the inclination (or staff) to think for themselves. But again, it's much more efficient to get things set right once rather than have 200 stations guessing. It's the getting it right in the first place that has been a problem.


What's different about the LA O&O(s)?

I suspect that was not an uncommon situation. With NBC getting more complaints about audio levels than the others on this forum one could question the validity of their recommendations. I would imagine that station GMs would not be happy having their station be the softest in town especially during the local news.


Not sure that the "loudest=best" assumption works any more. Increasingly viewers are complaining about content being too loud, rather than too quiet, in the UK.

If stuff is loud because it is over-compressed (i.e. pushed into the limiters) then it can be very wearing to listen to...

Ensuring a reasonable - though not excessive - dynamic range can be advantageous, as shows that are "easier" to listen to can retain audiences IMHO.

Two questions :

1. Do any of the big four networks support dynamic dial-norm (i.e. change the value on a show by show basis)

2. If they do, do affiliates have a way of passing this metadata (other than Fox - where I assume it just whizzes on through the splicer un-touched whether dynamic or not)?

3. Do any local stations manage their dial norm values for non-network (i.e. syndicated or local) content?

Ooops - that's three...

Not sure that the "loudest=best" assumption works any more. Increasingly viewers are complaining about content being too loud, rather than too quiet, in the UK.

If stuff is loud because it is over-compressed (i.e. pushed into the limiters) then it can be very wearing to listen to...

Ensuring a reasonable - though not excessive - dynamic range can be advantageous, as shows that are "easier" to listen to can retain audiences IMHO.Never said that loudest is best. I've commented on CBS's loud as well as NBC's soft. Most channels fall into the -25db to -27db range for dialnorm (probably most at the default -27db dialnorm since this is how the encoders are shipped). The program material on any given channel has about the same loudness range. The problem is that in addition to that variance the different static dialnorms make the overall level different. NBC is the softest (-23db) and CBS is the loudest (-31db) with the 8db difference between them (used to be 9db until NBC increased by 1db). Most everyone else is close to the default -27db. Instead of dialnorm making the situation better, it has actually made the situation worse. If NBC and CBS stations used dialnorm override to -27db it would IMO improve the situation.

1. Do any of the big four networks support dynamic dial-norm (i.e. change the value on a show by show basis)

Unless something changed recently -NO, all use static dialnorms.

2. If they do, do affiliates have a way of passing this metadata (other than Fox - where I assume it just whizzes on through the splicer un-touched whether dynamic or not)?

NBC and CBS both send metadata, ABC does not. NBC stations (http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/About/NBCBlockDiagram.pdf) get the metadata from the IRD data port output while CBS stations (http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/11_CBSBlockDiagram.pdf) get it from VANC or their Dolby E decoder (those links are a bit old but I think they are still valid). NBC has a static 5.1 mode while CBS uses 2.0/5.1 dynamic switching. Fox network is in 5.1 with rare exceptions and synthesizes all 2.0 material to 5.1. Some O&O ABC stations do that too.

3. Do any local stations manage their dial norm values for non-network (i.e. syndicated or local) content? If they do it is rare. None that I have seen.

Never said that loudest is best. I've commented on CBS's loud as well as NBC's soft. Most channels fall into the -25db to -27db range for dialnorm (probably most at the default -27db dialnorm since this is how the encoders are shipped). The program material on any given channel has about the same loudness range. The problem is that in addition to that variance the different static dialnorms make the overall level different. NBC is the softest (-23db) and CBS is the loudest (-31db) with the 8db difference between them (used to be 9db until NBC increased by 1db). Most everyone else is close to the default -27db. Instead of dialnorm making the situation better, it has actually made the situation worse. If NBC and CBS stations used dialnorm override to -27db it would IMO improve the situation..

The regulations (which have the force of law) say that the Dialnorm must match the measured loudness. Having everyone be equally wrong doesn't count. Re-calibrating all speedometers won't change the actual speed.

1. Do any of the big four networks support dynamic dial-norm (i.e. change the value on a show by show basis)

Unless something changed recently -NO, all use static dialnorms..

Well, CBS, Fox, and NBC support dynamic dialnorm (and all metadata) on their network feeds. They just have their systems locked down with static Dialnorm values.

2. If they do, do affiliates have a way of passing this metadata (other than Fox - where I assume it just whizzes on through the splicer un-touched whether dynamic or not)?

NBC and CBS both send metadata, ABC does not. NBC stations (http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/About/NBCBlockDiagram.pdf) get the metadata from the IRD data port output while CBS stations (http://www.dolby.com/uploadedFiles/zz-_Shared_Assets/English_PDFs/Professional/11_CBSBlockDiagram.pdf) get it from VANC or their Dolby E decoder (those links are a bit old but I think they are still valid). NBC has a static 5.1 mode while CBS uses 2.0/5.1 dynamic switching. Fox network is in 5.1 with rare exceptions and synthesizes all 2.0 material to 5.1. Some O&O ABC stations do that too.

3. Do any local stations manage their dial norm values for non-network (i.e. syndicated or local) content? If they do it is rare. None that I have seen.
All NBC stations that use network-supplied metadata are supposed to correctly set Dialnorm for their local programming. Some do, but obviously not all.

The regulations (which have the force of law) say that the Dialnorm must match the measured loudness. Having everyone be equally wrong doesn't count. Re-calibrating all speedometers won't change the actual speed.Does it make sense to have to recalibrate the speedometer for each road driven? That is similar to having viewers needing to recalibrate their volume control to the average loudness on each channel due to different static dialnorm values.

ATSC has been in operation for a decade now. How many citations have been handed out for dialnorm violation? Maybe after a couple fines compliance would happen quickly. But it hasn't been a priority and there's no indication that it will be anytime soon. The networks won't agree on static values and the stations, with the exception of FOX, have the final say. Fox is near the center so it's not so bad.
Well, CBS, Fox, and NBC support dynamic dialnorm (and all metadata) on their network feeds. They just have their systems locked down with static Dialnorm values.Their network distribution and station interface supports it, but their workflow for playout evidently does not.
All NBC stations that use network-supplied metadata are supposed to correctly set Dialnorm for their local programming. Some do, but obviously not all.Kind of a joke to tell the stations to do that while the network doesn't. The stations have the same issue with the material they receive with the variance in levels, and probably have less time and resources than the networks to deal with it.

I fail to understand why the lack of compliance for setting the dialnorm to match program material needs to be exacerbated by a variance in static dialnorm values. The former issue will require time for standards and equipment support to be in place, while the latter could be dealt with now with a simple setting change that would take a minute to implement. So far there has not been a catalyst for proper dialnorm support which would probably require both monetary and time expense. I suspect that will require government threat of fines or legislation. Good standards don't seem to be a motivation.

Does it make sense to have to recalibrate the speedometer for each road driven? That is similar to having viewers needing to recalibrate their volume control to the average loudness on each channel due to different static dialnorm values.

ATSC has been in operation for a decade now. How many citations have been handed out for dialnorm violation? Maybe after a couple fines compliance would happen quickly. But it hasn't been a priority and there's no indication that it will be anytime soon. The networks won't agree on static values and the stations, with the exception of FOX, have the final say. Fox is near the center so it's not so bad.
Their network distribution and station interface supports it, but their workflow for playout evidently does not.
Kind of a joke to tell the stations to do that while the network doesn't. The stations have the same issue with the material they receive with the variance in levels, and probably have less time and resources than the networks to deal with it.

I fail to understand why the lack of compliance for setting the dialnorm to match program material needs to be exacerbated by a variance in static dialnorm values. The former issue will require time for standards and equipment support to be in place, while the latter could be dealt with now with a simple setting change that would take a minute to implement. So far there has not been a catalyst for proper dialnorm support which would probably require both monetary and time expense. I suspect that will require government threat of fines or legislation. Good standards don't seem to be a motivation.

The last thing anyone (including the ATSC) wants to see happen is for the government to get involved in loudness.

Short-term bandaids, while seemingly easy to implement, are no substitute for a desire to understand what it takes to do audio in DTV. Too many people think, "Ah, it's just the same as analog" and leave it at that.

Standards exist, equipment to implement it exists, there is just a surprising lack of desire to do anything about it (except complain, and even broadcasters do that.)

Standards exist, equipment to implement it exists, there is just a surprising lack of desire to do anything about it (except complain, and even broadcasters do that.)What common standard is in use to embed AC3 metadata from production through delivery? None that I know of. It's made even worse by the fact that much of the programming still originates from SD sources. Using Dolby E audio (NBC) or proprietary VANC metadata (CBS) could work, but these are not approaches in widespread use. The fact that even with these systems in place that both networks still use a static dialnorm would indicate that issue is more complex than that. Having a system in place industry wide any time soon appears unlikely. At this point it's on just on the wish list.

The range of loudness on each channel (at least broadcast) of the actual audio (not scaled by dialnorm) is about the same and therefore the same static dialnorm value would have the same validity on all of them. NBC may be an exception as they seem to have other audio level issues besides just their dialnorm. Having an 8db variation from loudest to softest dialnorm is just compounding the inadequate dialnorm association to each program element with more bad engineering practices. In particular NBC and CBS stations don't need to be the softest or loudest in town and can join the average loudness range that the others are using. It seems one station to do so is, oddly enough, the CBS LA O&O.

The program elements which typically deviates the most from the average program loudness are commercials and promos. An effort to better match their levels to the program would probably solve the most glaring loudness mismatches on a given channel. Even accomplishing that seems difficult.

I will agree that the lack of desire to correct this is surprising.

What common standard is in use to embed AC3 metadata from production through delivery? None that I know of.
Dolby first developed Dolby E because they knew what the limitations of the infrastructure were back in 1999 (and still are.) Dolby E will carry metadata (and audio:D) inside an AES "wrapper." Several standards reference this: SMPTE 299, 337, amd 338.

Some networks decided that they didn't want to use audio data rate reduction, but did want to pass metadata, so they decided to embed just the metadata into the V-ANC area of the HD-SDI signal. This area of the signal is specified in SMPTE 291. Embedding audio metadata is referenced in a family of standards called SMPTE 2020-1, -2, and -3. CBS uses SMPTE 2020-3, everyone else uses SMPTE 2020-2. Audio metadata itself is referenced in SMPTE 2020-1.
It's made even worse by the fact that much of the programming still originates from SD sources.
Different problem. These stereo sources could be sent as-is (in stereo) or upmixed. I would prefer not to upmix, as it could cause problems when someone downmixes at home (i.e., listens in stereo!)
Using Dolby E audio (NBC) or proprietary VANC metadata (CBS) could work, but these are not approaches in widespread use.
All the networks, and many cable network, use Dolby E for program backhaul, so the metadata path is there. While Dolby E may be proprietary, audio metadata is not, and is covered in several standards and descriptive documents. V-ANC carriage is ubiquitoius for captioning, there just isn't the same interest in audio metadata as there is for captions. (Few have realized that correct audio metadata and captions are BOTH mandated by the FCC...)
The fact that even with these systems in place that both networks still use a static dialnorm would indicate that issue is more complex than that. Having a system in place industry wide any time soon appears unlikely. At this point it's on just on the wish list.
Ten years into this process, and with analog being turned off in less than six months, to have this just on a "wish list" is almost criminal. Three of the "big" networks have a way to deliver audio metadata, but their inability to make it accurate indicates a lack of ability to go the "last mile" towards getting it right. The engineers seem to have it right. The operations people haven't yet figured out how to work with it.

Those networks that don't provide audio metadata at all are still operating in the 1970s.
The range of loudness on each channel (at least broadcast) of the actual audio (not scaled by dialnorm) is about the same and therefore the same static dialnorm value would have the same validity on all of them. NBC may be an exception as they seem to have other audio level issues besides just their dialnorm. Having an 8db variation from loudest to softest dialnorm is just compounding the inadequate dialnorm association to each program element with more bad engineering practices. In particular NBC and CBS stations don't need to be the softest or loudest in town and can join the average loudness range that the others are using. It seems one station to do so is, oddly enough, the CBS LA O&O..
Variations between channels and variations within the same channel are different problems, but both can be fixed at the same time if each network just makes their own programs play by the rules. Excuses about cable and satellite all fall by the wayside, as operating in digtal can fix these problems, too. (Unless a provider intentionally messes with part of the bitsream without realizing the effect on the entire system.)
The program elements which typically deviates the most from the average program loudness are commercials and promos. An effort to better match their levels to the program would probably solve the most glaring loudness mismatches on a given channel. Even accomplishing that seems difficult..
True, but that is usually chalked up to a hands-off policy of receiving and airing commercials as files. The old days of having someone there to check the spots before they air is gone, and there is no interest in going back. File-based tools exist, and cable is making great strides using them, but there is much more work to be done.
I will agree that the lack of desire to correct this is surprising.
Yes, but that is quite an understatement!

Embedding audio metadata is referenced in a family of standards called SMPTE 2020-1, -2, and -3. CBS uses SMPTE 2020-3, everyone else uses SMPTE 2020-2. Audio metadata itself is referenced in SMPTE 2020-1.

All the networks, and many cable network, use Dolby E for program backhaul, so the metadata path is there. While Dolby E may be proprietary, audio metadata is not, and is covered in several standards and descriptive documents. V-ANC carriage is ubiquitous for captioning, there just isn't the same interest in audio metadata as there is for captions. (Few have realized that correct audio metadata and captions are BOTH mandated by the FCC...)Yes there are technical standards, but not an agreed upon standard methodology to pass the dialnorm from start to end. Dolby E is used for backhauls but at least in my experience it's typically used as an audio transport and the metadata is not used. Tape delivery is probably best with discreet tracks as Dolby E requires two frames of video delay somewhere to compensate the encode and decode delay. I think VANC is the best approach but it has its drawbacks in that it must be supported through the entire path and not get stripped off. But how will it take before a common system is in place?

The engineers seem to have it right. The operations people haven't yet figured out how to work with it.I don't think the operations people have much to do with it. Engineering is who puts the tools in place and managers decide whether it's cost and time effective. These sort of decisions come from upon high and they have apparently not shown much interest.

Those networks that don't provide audio metadata at all are still operating in the 1970s.It seems technically feasible that ABC could have passed the network metadata to the station encoder. The dialnorm can be ignored by the network decoder to avoid double dialnorm attenuation. They are moving to a new system but I don't know if it includes plans for metadata. NBC has it in place but what is it used for? They don't even use dynamic 2.0/5.1 switching any more. Fox upconverts all stereo to 5.1 but as mentioned they do risk degrading the stereo on stereo sets that downmix.

Variations between channels and variations within the same channel are different problems, but both can be fixed at the same time if each network just makes their own programs play by the rules.But they don't make most of their own programs and usually have a policy of not altering the levels of delivered material. Besides does each network have a different mixing level? I've not heard of that. The same mixers are often working on shows for different networks. Imagine the nightmare of having each network requiring a different level for delivery.

True, but that is usually chalked up to a hands-off policy of receiving and airing commercials as files. The old days of having someone there to check the spots before they air is gone, and there is no interest in going back. File-based tools exist, and cable is making great strides using them, but there is much more work to be done.And this is IMO where most of the problem lies. Yeah some reality shows might be somewhat louder than some dramas, but it's the commercials that are the loudness villains. Fix that problem and most of the inter-program level problems will be dealt with.

I agree that a major effort should be made to make the dialnorm correct. However I was thinking that if dialnorm was assigned properly to commercials, is it possible they may try to compress them even more to offset the volume reduction?

The networks have not yet made this priority. However viewers do not watch OTA networks directly (aside from Fox), they watch stations. Until the networks and program providers can get their dialnorm act together, I think the viewers are better off without the overall loudness differences between channels especially from NBC and CBS. I don't see how doing so will delay the networks from doing proper implementation. When they do it is a simple change to disable the override.

So what is it going to take to make proper dialnorm values a priority? Pretty please doesn't seem to work.

Yes there are technical standards, but not an agreed upon standard methodology to pass the dialnorm from start to end. Dolby E is used for backhauls but at least in my experience it's typically used as an audio transport and the metadata is not used. Tape delivery is probably best with discreet tracks as Dolby E requires two frames of video delay somewhere to compensate the encode and decode delay. I think VANC is the best approach but it has its drawbacks in that it must be supported through the entire path and not get stripped off. But how will it take before a common system is in place? .

Networks will never agree on one way to do things. That's why we have 720p and 1080i. True, Dolby E has delay, but so do frame syncs and VTRs. So does MPEG. The VTR manufactures "fix" this for you. Some manufacturers "un-fix" it and allow the system to go forward, but there are other issues. "First and Ten" for football and virtual billboards for baseball and other video tricks delay the video, but you never hear someone refuse to use it because of the delay. It goes back to audio being the poor stepchild if television, but that's just an excuse. Again, somehow closed captioning survives. Why? How?

I don't think the operations people have much to do with it. Engineering is who puts the tools in place and managers decide whether it's cost and time effective. These sort of decisions come from upon high and they have apparently not shown much interest.

It seems technically feasible that ABC could have passed the network metadata to the station encoder. The dialnorm can be ignored by the network decoder to avoid double dialnorm attenuation. They are moving to a new system but I don't know if it includes plans for metadata. NBC has it in place but what is it used for? They don't even use dynamic 2.0/5.1 switching any more. Fox upconverts all stereo to 5.1 but as mentioned they do risk degrading the stereo on stereo sets that downmix..

Believe it or not, part of the reason is a series of (poor?) decisions made without regard for audio or metadata, and engineers are then stuck trying to pick up the pieces.

But they don't make most of their own programs and usually have a policy of not altering the levels of delivered material. Besides does each network have a different mixing level? I've not heard of that. The same mixers are often working on shows for different networks. Imagine the nightmare of having each network requiring a different level for delivery..

Exactly the reason for Dialnorm. It is unrealistic to expect TV programs to have the same loudness, considering there is no common practice in mixing them (unlike films.) If, somehow, they do agree on a mixing level, then a common Dialnorm value will work. The system works either way.

And this is IMO where most of the problem lies. Yeah some reality shows might be somewhat louder than some dramas, but it's the commercials that are the loudness villains. Fix that problem and most of the inter-program level problems will be dealt with.

I agree that a major effort should be made to make the dialnorm correct. However I was thinking that if dialnorm was assigned properly to commercials, is it possible they may try to compress them even more to offset the volume reduction?.

Commercial producers have never been able to out-shout each other in analog TV because of the audio processing used at each station. They've figured other ways to make their commercials stand out.

The networks have not yet made this priority. However viewers do not watch OTA networks directly (aside from Fox), they watch stations. Until the networks and program providers can get their dialnorm act together, I think the viewers are better off without the overall loudness differences between channels especially from NBC and CBS. I don't see how doing so will delay the networks from doing proper implementation. When they do it is a simple change to disable the override.

So what is it going to take to make proper dialnorm values a priority? Pretty please doesn't seem to work.

The networks are talking about this, so this might be the way to get it right first, rather than have hundreds of stations try to guess right.

We're both on the same side here. There is much more work to do. Broadcasters have just blown the lead they had. They could have fixed this 5-10 years ago while no one was watching. Too late now.

Networks will never agree on one way to do things. That's why we have 720p and 1080i. True, Dolby E has delay, but so do frame syncs and VTRs. So does MPEG. The VTR manufactures "fix" this for you. Some manufacturers "un-fix" it and allow the system to go forward, but there are other issues. "First and Ten" for football and virtual billboards for baseball and other video tricks delay the video, but you never hear someone refuse to use it because of the delay. It goes back to audio being the poor stepchild if television, but that's just an excuse. Again, somehow closed captioning survives. Why? How?Because everyone uses the same standard. We stuck with what worked. And besides, we couldn't get Garrett Morris for every show.

Frame syncs add delay but they usually have a path for both audio and video (embedded makes that alot easier :D). Obviously networks have had different approaches, especially on distribution. Even with analog, FM deviation could be different (NBC was super wide). Audio levels could be 0db, +4db or +8db. But in terms of production what went on tape was pretty much standard.

Dolby E on tape delivery, while not rare, is not the most common appraoch especially now with 12 channels on SR. It would work if everyone accepted Dolby E delivery but they don't. So if VANC becomes the method everyone uses it's going to take a while.

I found it interesting in the past that NBC would use Dolby E internally and then break it out to discreet pairs for network distribution, while CBS used discreet pairs internally and then encoded to Dolby E for network distribution.

Exactly the reason for Dialnorm. It is unrealistic to expect TV programs to have the same loudness, considering there is no common practice in mixing them (unlike films.) If, somehow, they do agree on a mixing level, then a common Dialnorm value will work. The system works either way.

Commercial producers have never been able to out-shout each other in analog TV because of the audio processing used at each station. They've figured other ways to make their commercials stand out.But there is no denying that commercials are usually louder. Mixing levels on shows do vary somewhat but are still usually within a reasonable range. Complaints about levels changing between shows are the rare exception compared to the commercials are too loud.

The networks are talking about this, so this might be the way to get it right first, rather than have hundreds of stations try to guess right.

We're both on the same side here. There is much more work to do. Broadcasters have just blown the lead they had. They could have fixed this 5-10 years ago while no one was watching. Too late now.I would say we certainly agree that proper dialnorm implementation is the right way to go and hope this happens soon. Where we diverge is what to do in the meantime. I really see the issue as the two bookend networks - NBC and CBS - for having such a wide difference in loudness due to their choice of dialnorm values. It's not like 100s of stations need to be coordinated to override their dialnorm but rather it becomes an individual station's choice. If they feel they want to be more in line with the loudness of the other stations then it's an easy change. If they want to continue what they are doing than that can be their choice too. But I think most stations don't want to be thought of as one of those annoying channels that one always have to change their volume control for. While too loud is obnoxious, I think that being much softer than the average puts a station at a greater disadvantage. The default value of -27db is probably where most encoders are set to so that would be a good starting point. At some future point when dialnorm is properly implemented they can switch back to the external dialnorm and DRC. However at that point there may be other measures that need to be taken so all sources, local and network, will comply.

I don't see this as a bandaid so much as eliminating an unnecessary discrepancy. Stations can take care of the interchannel issue now while networks and program providers take care of proper program element implementation later. I see that as a win-win.

This and AFD are the two big issues I think US broadcasters and networks missed. At least there is some movement on AFD. As for dialnorm it might come to "Open up it's the dialnorm police". The story you are about to see is true; the dialnorms have been changed to protect the innocent.

Because everyone uses the same standard. We stuck with what worked. And besides, we couldn't get Garrett Morris for every show.

This and AFD are the two big issues I think US broadcasters and networks missed. At least there is some movement on AFD.
I can think of at least a half-dozen different ways that live, scripted, and taped programs get their captions on the air. The permutations are mind-numbing, but it gets done because there was a perceived need, mandate, or law to do so. And don't get me started on the final link in the chain and the 608-708 problems...

Frame syncs that can handle embedded audio have only been around for a year or two. Frame syncs, in general, have been around since the late 1970s, but for a long time they were too expensive to have more than one. Audio embedding was also expensive. Now that's changed, but for 25 years, frame syncs were a big part of the problem for lip sync (but that's a different discussion!)

Engineering departments at stations have been forced by station management to be interrupt-driven, responding only to the biggest problems. Audio isn't high on the list of most people making that list. I sometimes wonder if anyone really watches and listens to their DTV station. People only watch it in the lobby of the station.

AFD is, for all intents and purposes, video metadata. It is almost exactly analogous to audio metadata; it is just used for pictures. I see a similar lack of interest in AFD among the networks. However, because it has to do with picture, there is a chance that people may pay attention this time. Once they do, then maybe people will see how audio metadata can also be used. Again, it's "audio follow video."