Why is the audio level on DVDs often so low?

Is there some industry reason for this? It makes no sense to me that they would not at least normalize the soundtrack to 0dB. And yet, since I do virtually all DVD watching on a computer, I have to crank the powered outboard speakers all the way up, and sometimes it still isn't loud enough to get the whispered or low-talking dialog.

Likewise, if you're watching on a television monitor, you turn the volume way up to watch the movie, but then when you go back to broadcast fare, it's way too loud.

So, I guess my question is why DVDs are routinely mastered with 12 dB of headroom? Sometimes a bit better, sometimes worse, but generally the levels are not what I'd call optimum.

 

This has frustrated me for years. Dialogue levels in the basement, music and FX through the roof. Gets really annoying having to do a "live mix" while I watch things.

I've been told that this is a 5.1 thing, and if I had a surround setup (I don't), I could just boost the center channel. Wouldn't it just make more sense to create a balanced mix and then let the consumer tweak it as they see fit?

 

Dynamic range.

-Bill

 

Dymanic Range, the thing we all think we want tons of with music.....

Seriously over compressed is just as bad as no compression with some things.

I have a couple CDs with NO compression and live music, and its all or barely nothing volume levels. What sounds cool outside live does not translate to cool sounding in a living room. Its actually hard to listen to at any normal volume.

Compression is your friend at times.....!

 

Agreed, a little compression will help even out those muddy and blistering audio levels...

 

I have never experienced this problem, and I've been buying DVDs since 1997.

 

That's not an answer. If you normalized the highest peak to 0dB, it would not change the relative difference between the loudest and softest sounds.

This is what I think should have been done with the Beatles remasters -- but they raised the levels to the point that some of the peaks had to be compressed. That's not what I'm talking about. I'm talking about simply letting the highest level be 0dB, so that the overall levels are not absurdly low -- without changing the dynamic range at all.

 

Combination of dynamic range and the fact that even powered PC speakers are usually pretty weak. I know I have trouble with certain films. Most of the soundtracks can be boosted a bit without clipping but beyond that you need to dynamically compress it.

 

DVDs are normal...everything else is to loud...starting from the days of home VHS!

 

me neither! and I have thousands of movies...

 

The level isn't low.

Films have a lot more dynamic range than most music, and most people do not have the systems or acoustics to play back a proper 5.1 movie mix, and most people have not properly calibrated their surround systems either.

A high-performance surround system in an acoustically treated space that's properly calibrated and played at (or near) reference level (0dB) has no issues with dialogue intelligibility.

This is a perennial question that has as much merit as the "why does my widescreen TV still show bars?"



If you don't like dynamic range, then you can engage midnight mode or other third-party dynamic range compression tools (like Audyssey Dynamic Volume) that are available on many AVRs.

The fact that the OP is trying to listen to movies on unnamed 'computer speakers' and is having problems should not surprise anyone.

 

It is a problem if you're downmixing a surround sound audio track to stereo (or mono). Obviously, if the dvd has it, it's better to listen to the dedicated stereo tracks since presumably the mix will be more suited for systems without surround sound. But I have noticed, as you mention, having to boost the center channel so I can hear dialog better and not have FX bother me by being too loud. I think my system set up is generally okay because there are plenty of surround mixes that sound fine to me without tweaking, but some just seem too heavily weighted towards the surround channels and subwoofer.

 

Other than a few rare instances, I haven't experienced this problem either. I certainly don't want blu-ray/dvd audio tracks to start getting hammered the way CD's do.

For what discs do you have this problem? Are you sure your speakers and everything else are set up right?

Having a properly positioned center speaker really does help with the dialog.

 

It's midly annoying and odd that I have to drastically alter the volume on my preamp when I go from playing CDs to playing DVDs/BluRays


but


what I CANNOT fathom is why they can't keep the volume stable on the same disc!! I have a lot of DVDs/BluRays where the main menu is MUCH louder than the film. And even some TV series where the volume has to be adjusted when playing different episodes! Or the main feature is one volume and the bonus features are much quieter. This HAS to just be carelessness, no?

One of these days I gotta get a preamp with remote-controlled volume.

 

Yep. Chris is completely right. The levels of modern CD's and digital files are too high because of limiting. DVD levels are set to an industry standard that is just right.

 

Hard to believe that people on an audiophile forum cannot understand that raising the maximum level to digital 0dB instead of -12dB does not necessarily compromise dynamic range -- it should not alter dynamic contrasts unless it is pushed to clipping. I am not complaining about wide dynamic range. I am complaining that when they encoded the sound at the mastering facility, they set the level too low. This is a problem for me on about 10% of DVDs. And I'm not alone. I don't want it compressed. It should just be a little louder. I cannot see any advantage in having the peaks only reach -12dB. I hoped some of the folks here who are closer to the video industry might have some insight into this practice.

 

What program are you using to identify that maximum peak volume is -12dB? And can you give us some examples of discs that measure like this?

 

I am not trying to sound like a jerk, but you are the one that is lacking understanding on this topic. I suggest you read this material. You will see that it is not a question of setting the gain too low on DVD's--rather, the effect you dislike is because of the allowance for dynamic range that is part of the Dolby Digital spec and authoring practices.

http://www.minnetonkaaudio.com/info/PDFs/DolbyDigital_Guidelines.pdf

You see, CD's and music files--and particularly rock music--do not have much dynamic range, at least, not much when compared to a movie soundtrack. An explosion in a movie could hit 0dB and that would be the peak, while the rest of the soundtrack is significantly more quiet. A rock song, on the other hand, is going to have nowhere near as great a difference between the loud and soft parts of the song, and therefore the average volume of the rock song, if the peak is also at 0dB, is going to sound a lot louder than the DVD.

During Dolby Digital authoring, the engineer can select dynamic range compression to obviate this somewhat, but the DVD soundtrack is still going to sound much quieter than a CD or mp3 file.

 

The reason why there is excessive dynamic range on many home video releases is because the sound design was made for the theater, where there is plenty of room to have the louds really, really loud. Not all films gets their audio redone to suit a home environment. So you have to ride the volume, up for dialogue, down for action, throughout the whole film. But many receivers have settings to compress these down so everything is more comfortable - try Denon, in particular.

 

I am not aware of any films nowadays that are significantly compressed or re-mixed for home use, thankfully. In the earlier days of DVD, certain DVD houses would apply a RE-EQ type filter to compensate for the playback in a smaller space and not through a perf screen, however my understanding is that this practice largely dissipated, and is not relevant to the issue of dynamic range or overall level.

DR compression of theatrical mixes for the home would be a travesty.

It is a significant challenge to reproduce a surround movie mix in the home, but it can be done and the results are exceptional. You just can't do it on the cheap, and you sure as heck can't do it on computer speakers...

 

Um. What are you talking about?

Where is this -12 coming from?

Film soundtracks are not mixed to a maximum. They're mixed so that dialogue is at a rather standard level (~-25 to about -31dbBFS) when listened to at full reference level, and dialnorm is set appropriately. If it's not a loud film, say it's only a drama with no bombastic action sequences, it will never come close to hitting the digital peak (0dBFS), nor should it. If you expect that every film should be mastered such that the loudest passage of that particular film should come very close to the digital peak, then you are not understanding the film world which does have a defined reference playback level, unlike audio which has no reference level.

 

Actually, they do go through a separate Q/C pass for home video, and some studios specifically require the mix to meet ITU and ATSC loudness standards. A special meter calibrates the average level, momentary loudness level, and long term program loudness with a specific number. Quite a few TV networks and channels (particularly PBS and Discovery) demand adherence to this spec, and Disney has done this for some time as well.

Here's a shot of one of the popular loudness meter plug-ins:



The problem is, you can still have a nasty-sounding mix that technically will pass all the loudness specs. So the numbers only tell part of the story.

I have personally had home video mixes kicked back from QC departments, specifically for momentary loud explosions and similar problems. One was from an Oscar-winning film (for Best Picture and Best Sound), and the studio forced us to limit it on a half-dozen places for gunshots, cannon explosions, and shotgun blasts. Nobody noticed, everybody loved it, and it got rave reviews. (This was also a film where the digital tracks became unplayable for technical reasons, and the 6-track analog Dolby SR was used instead. Go figure.)

Studios will routinely reject any movie where the loudest peak goes over -10dBfs, but I think they really need to be more aware of the problems with low-level dialog intelligibility. It's not so much that movies are too loud -- it's that low-level dialog scenes are too soft. You crank up your TV set or speaker system to hear the quiet scenes, and then BOOM, you get blown out of the room when the music or sound effects kick in. I believe the remixes on the old Star Trek shows are done this way, in my opinion. Way too dynamic for my tastes. Excessively wide dynamic range is not always a good thing.

 

^ For broadcast, yes of course, but not for disc. Things are not being crushed for DVD and BD, at least they shouldn't be on any competent major releases. There's no technical reason whatsoever to do that. There certainly is for broadcast use, however.

 

The solution to that is either a better system (and acoustics) or dynamic range compression.

You cannot listen to a film soundtrack properly in an untreated living room.

The user with a crippled playback system should deploy DR compression on their own, not foist that evil in the rest of us who want the original mix or close to it by compelling studios to go around crushing movie releases. Every receiver should have per standard some kind of DRC mode or 'night' mode. That's what it's for. RTFM and turn your night mode on.

I want the theatrical experience. I didn't build out a dedicated room to have some crummy 7dB of dynamic range on all my BDs because Joe Joey is trying to listen in a cement room on Bose cubes and wants everything to sound like The McLaughlin Group... :thumbsdn:

 

Yes, they should be, and often are. Most people do not have soundproofed rooms 100' across where they watch tv. The typical living room is a different sized space than a theater, and things need to be tailored to suit it. Ideally by the same person who did the theatrical mix.

Google the term "near field mix" to find plenty of interviews with filmmakers who strive to make the sound quality for the home release as good as the theatrical presentation.

Here's a better excerpt: