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Why bass management makes my life tedious

markus

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#81
Dolby Atmos for streaming is 1 bed (the LFE) and 12 objects. For the disc, it is 1 bed plus 16 objects.
I think the Dolby Atmos renderer guide says something like 11 to 15 output objects and one bed channel for the LFE.
 

markus

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#82
Things HAVE changed, you are just not aware it has. When Dolby TrueHD first showed up on Bluray, the encoder default for the LPF was off, and you had to turn it on. DTS HD Master Audio encoder default for the LPF was on, hence why you have never heard of Dts tracks having full range signals in the LFE. Today, Atmos and TrueHD encoder default is on, THAT is the change.
Good to know but what about all the old content? And why is the encoder LPF on LFE still optional?
 

krabapple

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#83
I certainly wouldn't consider this "normal" either. A feature mix could fail QC for having significant unfiltered content in the LFE.

It could very easily be a plain and simple oversight with no thought behind it. Not trying to excuse it, but with the best will in the world, workflows can get really messy sometimes and things slip through the net in the rush to get things out the door. ( I shouldn't say that, obviously my workflows are bullet-proof :p )
If it's an oversight it's pretty damn common.

I just examined the LFE of 83 Bluray, DVD-Audio, and SACD 5.1 mixes of music albums (not movies) that I own and have in ripped form.

More than a quarter of them (27/83) have full bandwidth content in their LFEs -- typically drum kit + bass -- even, in at least one case, guitar. The format (BR/DVDA,SACD) doesn't matter, there are examples in all three .

Another 9 have what sounds like extended bass i.e., above 120 Hz.

Another two have empty LFE (i.e., they are actually 5.0 in a 5.1 container)
 

markus

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#84
If it's an oversight it's pretty damn common.

I just examined the LFE of 83 Bluray, DVD-Audio, and SACD 5.1 mixes of music albums (not movies) that I own and have in ripped form.

More than a quarter of them (27/83) have full bandwidth content in their LFEs -- typically drum kit + bass -- even, in at least one case, guitar. The format (BR/DVDA,SACD) doesn't matter, there are examples in all three .

Another 9 have what sounds like extended bass i.e., above 120 Hz.

Another two have empty LFE (i.e., they are actually 5.0 in a 5.1 container)
Ups. Per @Soundmixer this must be older content?
 
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#85
No offense intended here. But your position is Static thinking. I personally have seen a huge move in the home theater area. Yes, agreed it represents a small portion of the market.
Actually, it is reality thinking. Static thinking would still have me back at Velodyne subwoofers. Adam, what you see may not be the entire picture, as the reality is the real growth in "home theater" is soundbars and weak subs. The real growth with subwoofers is in the mid-priced market, not at the high end.

No doubt that the current market is “Soundbar” centric, but the landscape is changing as more and more people decide to build out their own home theater.
If you look at the sales stat's, there hasn't really been any growth in the non-soundbar category of home theater. Speakers, subs, panels, and projectors sales slowed considerably in 2020. So what you see is viewed through a bubble when you look from 30,000ft.

Full disclosure “I am a self diagnosed “Basshead””. Just give us the full range Sound and let’s the buyers/users determine if they can and will reproduce it fully. I am completely adverse to the recent trend of low frequency neutering of Sound tracks. JMHO.
If you don't have a valid comparison (spectral graphs) of a cinema soundtrack and a disc-based soundtrack to compare, your statement is perpetuating a myth, and that is just not helpful. The is no evidence whatsoever, no valid comparison whatsoever that points to the reality there is any "neutering" of the bass of any soundtrack on disc. If you have a link to such a comparison, please by all means post it.
 
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#86
If it's an oversight it's pretty damn common.

I just examined the LFE of 83 Bluray, DVD-Audio, and SACD 5.1 mixes of music albums (not movies) that I own and have in ripped form.

More than a quarter of them (27/83) have full bandwidth content in their LFEs -- typically drum kit + bass -- even, in at least one case, guitar. The format (BR/DVDA,SACD) doesn't matter, there are examples in all three .

Another 9 have what sounds like extended bass i.e., above 120 Hz.

Another two have empty LFE (i.e., they are actually 5.0 in a 5.1 container)
Neither SACD nor DVD-A has standards on how to use the .1 channel. It can be a full-range height channel (Chesky), a full-range ground channel, or not used at all. The music industry does not have any standards on how the LFE is used overall. So no matter what release format you examine, how it is used for music will likely be all over the map.
 

AdamG247

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#87
Actually, it is reality thinking. Static thinking would still have me back at Velodyne subwoofers. Adam, what you see may not be the entire picture, as the reality is the real growth in "home theater" is soundbars and weak subs. The real growth with subwoofers is in the mid-priced market, not at the high end.



If you look at the sales stat's, there hasn't really been any growth in the non-soundbar category of home theater. Speakers, subs, panels, and projectors sales slowed considerably in 2020. So what you see is viewed through a bubble when you look from 30,000ft.



If you don't have a valid comparison (spectral graphs) of a cinema soundtrack and a disc-based soundtrack to compare, your statement is perpetuating a myth, and that is just not helpful. The is no evidence whatsoever, no valid comparison whatsoever that points to the reality there is any "neutering" of the bass of any soundtrack on disc. If you have a link to such a comparison, please by all means post it.
Here ya go. Possibly dozens or tens of dozen examples where the bass content has been cut/filtered/removed. Also many examples of where the original Blu-ray release had substantial Bass content but the reissue on UHD was bass managed. If that is a better term. And I did stipulate that this was Just my Opinion and personal observations.

https://www.avsforum.com/threads/th...n-movies-w-frequency-charts.2763785/page-1016

Here is an entire thread dedicated to this specific issue of Bass content in Blu-ray and UHD disc releases:
https://www.avsforum.com/threads/bass-eq-for-filtered-movies.2995212/
 

krabapple

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#89
Neither SACD nor DVD-A has standards on how to use the .1 channel. It can be a full-range height channel (Chesky), a full-range ground channel, or not used at all. The music industry does not have any standards on how the LFE is used overall. So no matter what release format you examine, how it is used for music will likely be all over the map.
Nor BluRay, apparently.

On DVDA and BluRay releases, there's access to mandatory lossy Dolby Digital and/or DTS 5.1 encoded versions of the same mix, for back compatibility. These versions applied a low pass filter for the LFE during encoding, as it typical for DD and DTS release. So the same disc can have different LFE depending on what version you choose to access from the disc....lossless or lossy.

It took me quite awhile to realize this is true, and what its possible effects might be. It's not something well known or acknowledged among surround music fans at all. They are forever ascribing nonsensical audio deficits to lossy 'Dullby' and DTS versus PCM/DSD, but are mostly ignorant of this actual difference.

And btw yet another issue with LFE content has been recently noted on some releases: lack of correct synchronization between it and other channels.

https://www.quadraphonicquad.com/fo...ave-a-lfe-issue-info-list-fixes-inside.30048/
 
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#91
Here ya go. Possibly dozens or tens of dozen examples where the bass content has been cut/filtered/removed. Also many examples of where the original Blu-ray release had substantial Bass content but the reissue on UHD was bass managed. If that is a better term. And I did stipulate that this was Just my Opinion and personal observations.

https://www.avsforum.com/threads/th...n-movies-w-frequency-charts.2763785/page-1016


Here is an entire thread dedicated to this specific issue of Bass content in Blu-ray and UHD disc releases:
https://www.avsforum.com/threads/bass-eq-for-filtered-movies.2995212/
These links were brought up earlier, and there is a problem with both. The frequency charts are not comparison charts, they are isolated spectro-graphs that don't really offer any context except for visual demonstration.


Neither link shows any comparison between the original cinema printmaster and the disc release. Without that comparison, there is no way anyone can come to the conclusion that something went wrong in the transfer from the printmaster to the disc. Secondly, you cannot compare a non-immersive soundtrack to an Atmos soundtrack without confirming both came from the same master, the same mixing and mastering studio, with the same equipment, and the same mixer. Without this data, these comparisons lack credibility.
 
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#92
Nor BluRay, apparently.

On DVDA and BluRay releases, there's access to mandatory lossy Dolby Digital and/or DTS 5.1 encoded versions of the same mix, for back compatibility. These versions applied a low pass filter for the LFE during encoding, as it typical for DD and DTS release. So the same disc can have different LFE depending on what version you choose to access from the disc....lossless or lossy.
Bluray is just a home release format. You can follow best practices, or not, the release format is irrelevant.

It took me quite awhile to realize this is true, and what its possible effects might be. It's not something well known or acknowledged among surround music fans at all. They are forever ascribing nonsensical audio deficits to lossy 'Dullby' and DTS versus PCM/DSD, but are mostly ignorant of this actual difference.

And btw yet another issue with LFE content has been recently noted on some releases: lack of correct synchronization between it and other channels.

https://www.quadraphonicquad.com/fo...ave-a-lfe-issue-info-list-fixes-inside.30048/
You are conflating two different things here trying to make a point. The music industry is not the same as the film industry. You keep presenting music to support your point, and I have already said it has no standards. The incorrect synchronization of the LFE with the mains can occur, but using the word "some" in regards to releases does not describe a global issue. I think you are overstating your point here without evidence that extends beyond some music releases.
 
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#93
Seemed like all the internet direct sub companies (the ones making the good stuff) got slammed with orders in the summer of 2020 and units were out of stock for some time.
Slammed with orders doesn't mean much without actual order numbers. If I only sold 25 high-end subs a month, and suddenly for several months I am selling 40 a month, that can be described as being slammed. Context is important here. Either number is a drop in the bucket compared to the sales of Polk and Klipsch subwoofer which are sold EVERYWHERE.

It is likely sourcing parts became an issue since these companies do not keep a lot of stock on hand. So being sold out doesn't mean very much under those conditions.
 
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#94
Why would you or he think that?

The 5.1 mixes were all done in the last 20 years, sourced from multitracks recorded in the last 60 years.
Thank you for making my point. 20 years ago is not exactly yesterday or the day before, or even the last 10 years. Once again, you are talking about music that has no standards, not film which does.
 

adc

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#95
Very interesting thread, and makes me feel vindicated for sticking with 2.1, in a music-first configuration.

I appreciate the nod to "artistic liberty" with sound effects as well; i.e., handguns that sound like shotguns (and make clicking noises every time they're touched or leveled). Same reason tires squeal on gravel; knives go "shinggg" every time they're drawn, even from a leather scabbard; and leading men's voices are usually heavily processed to sound deep and authoritative, even outdoors, without regard for credible, scene-appropriate acoustics. Once you notice these things, you can notice nothing else, and it becomes insanely distracting.

I just don't see the point in bothering to care about fidelity in movie sound reproduction when even presented as intended, it's just silly, and more often subtracts from, rather than adds to, enjoyment of the story (which for me is still the point). But that's just me, and I'm a crusty old fart.

Regardless: I definitely appreciate learning of the contortions an engineer goes through to accommodate unpredictable consumer environments. Hat tip for caring about excellence in the face of such adversity...
 
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krabapple

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#96
Thank you for making my point. 20 years ago is not exactly yesterday or the day before, or even the last 10 years. Once again, you are talking about music that has no standards, not film which does.
I repeat: they have been released *in the last 20 years*. It doesnt mean they are all 20 years old. It means, DVDA and SACD have been around since 2000 or so, followed much later by BluRay music releases. So, a 20 year span of time. Some of the releases that have full range LFE are just a year or two old. Some are two decades old. Age has nothing to do with it....if that was your point.
 
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krabapple

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#98
Bluray is just a home release format. You can follow best practices, or not, the release format is irrelevant.

You are conflating two different things here trying to make a point. The music industry is not the same as the film industry. You keep presenting music to support your point, and I have already said it has no standards. The incorrect synchronization of the LFE with the mains can occur, but using the word "some" in regards to releases does not describe a global issue. I think you are overstating your point here without evidence that extends beyond some music releases.
I'm not 'conflating' a thing, I never claimed or even implied that the practices I'm describing on 5.1 music releases, have been found on movie releases. Nor did I say anything about anything being a 'global issue'. That seems to be your imagination.

You mad because I'm talking about music release LFE here? Is this thread only allowed to be about movie soundtracks? If so, let me know, officer. .
 

krabapple

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I thought this tread was going about movie soundtracks, so yes to bring in music LFE in seems a bit of topic.

From my first paragraph of my post on the thread:
"Possibly this issue deserves a separate thread so as not to dilute this one "
The post proved several replies, but no one chimed in on that point.
If that's the feeling now, I'm happy to work with a moderator to fork this topic off to a new thread.


OP's contribution and Soundmixer's are highly interesting imho
I can't fathom why you would need to proclaim that. I wasn't shutting down their discussion.
 
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