Lennon 'Gimme Some Truth' 5.1 Audio Levels - DTS vs DD

[ar surround]

Thanks to all for the comments. I wonder if anyone has considered ripping the 7.1 True HD stream and then combining the surrounds and rears in Audacity to see if the resulting 5.1 "downmix" is acceptable. I won't be able to try doing this until after Christmas.

(Based on playing around with the Abbey Road 7.1 True HD stream, the Oppo 205 won't play 7.1 FLAC. It will recognize 7.1 WAV, but the resulting mixdown to 5.1 is missing "stuff" in the surrounds.)

 

[Which_One_Is_Pink]

John was waiting for me when I got home today, he says he will be staying for a while

 

[atomicdog]

The Dolby Atmos stream included on the Blu-Ray includes a series of embedded 'core' audio streams to ensure compatibility for listeners with older equipment. If you have an older AVR that pre-dates Dolby Atmos, it will play back in 7.1 Dolby TrueHD. If you have an even older AVR that pre-dates Dolby TrueHD, it will play back in 5.1 Dolby Digital.

Much appreciated.

 

[ssully]

This post only pertains to the two 5.1 versions on the 2020 release John Lennon - Gimme Some Truth.
It has nothing to do with the Atmos or 7.1 tracks. Apparently, those are fine and awesome.

? hasn't that been shown *not* to be the case?
aiui, the only surround version shown not to have been compressed further in dynamic range is the DD 5.1 .

Correct or not?

 

[JonUrban]

? hasn't that been shown *not* to be the case?
aiui, the only surround version shown not to have been compressed further in dynamic range is the DD 5.1 .

Correct or not?

I have no idea really. I just keep hearing from "Atmos" equipped guys here that the Atmos is fine. I don't do Atmos, so I don't want to get caught up in that argument. I will stay with my nice little DD 5.1 rip of the thing and be happy.

 

[jimfisheye]

The Atmos mix may sound fine with nothing else to compare it to. There's still hi-fi sound in a general sense in the slammed mastering. It clearly has the same damage as the dts ma and stereo streams though. If we didn't have the original raw mix delivered to us in the dd stream to compare to, there'd be no way to see this and call this with no uncertainty like we can here. It would just present as a front heavy so-so mix. Still hitting more or less "pro" fidelity marks.

The 7.1 core of the Atmos mis is distorted to high hell exactly like the other damaged streams. That 7.1 core comes right out of the file set on the disc. This is not a file that is derived and written to memory or hard drive on the fly - what would need to be the case for it to get damaged in some form of operator error. The height and object elements are what get folded down on Atmos setups with less than the full array of height and object channels. The 7.1 core remains static and is delivered on the disc.

The "mastered" (quotes denote opinion) mixes are a good 12db or so louder than the dd stream. Use and understanding of a volume control feature is required here.

I'm just repeating myself now. The evidence is right here in the disc. You can examine and listen to all this too. Volume control use is required. Probably a computer based media center too. There's little chance of working the audio streams intentionally with stand alone hardware and certainly no way to A/B two things with volumes matched.

Seeing some of the responses to this one (a recall candidate if there ever was one)...
Maybe I'll start mastering mixes to -7 LUFS and just call it a day. 8 bit should be fine too. Don't worry, I'll put the final master in LPCM or dts ma on a bluray so nobody notices.
It's frustrating to realize I could 100% get away with something like that and probably get good reviews!

This is messed up too because the actual mix that snuck out in the dd stream is aledigedly what everyone says they want! A nice warm full blooded mix with just an much oomph in the rears as the front. Nothing shrill or hyped sounding.

 

[fredblue]

is it truly worthy of a recall? i mean, the label could argue the discs are not defective in that "they play ok", etc..

 

[jimfisheye]

is it truly worthy of a recall? i mean, the label could argue the discs are not defective in that "they play ok", etc..

Oh yeah! If I was the mix engineer I'd be having an aneurysm! The content is in fact severely damaged and thus defective. It alters the mix drastically and puts it in a whole different league. (Cheap blow off corporate sounding.) The clearly unintentional inclusion of the actual undamaged mix there to call attention to it and reveal the whole thing seals the deal. There's no way to save face here in light of that.

Now, knowing how easy to please some listeners apparently are and how things end up working often enough, I wouldn't be surprised if they recalled it but instead of correcting it, replaced the raw mix with another destroyed copy for the dd stream just to hide the mistake!

I suppose to be fair, the client could have not liked the mix as turned in and requested the mastering engineer to make it loud and corporate sounding. Maybe we should be blaming Yoko for this!? Aha!

See why I'm asking for some actual accomplished Atmos mixes first before I go through the effort of hooking up more speakers? It's amateur hour right now aimed at movies and consumers with soundbars. LOUD is still in vogue.

 

[EricKalet]

Oh yeah! If I was the mix engineer I'd be having an aneurysm! The content is in fact severely damaged and thus defective. It alters the mix drastically and puts it in a whole different league. (Cheap blow off corporate sounding.) The clearly unintentional inclusion of the actual undamaged mix there to call attention to it and reveal the whole thing seals the deal. There's no way to save face here in light of that.

I'll have to go back and listen to the DTS 5.1. Right now I'm playing the 7.1 Atmos and it sounds fine to me. But I'm no golden ear either.

 

[perzon57]

Well neither is he,he does not even have a Atmos setup but he has seen that it sounds like shit.

 

[atomicdog]

Subjectively speaking, in A/B comparisons of these Lennon tracks, which have been remixed and remastered before, and compared against various stereo versions, I found no degradation of the sound and some improvement in terms of clarity (less muddiness). The surround versions, which place Lennon's vocals in the center channel, as was the case on the Imagine remixes, only add to that clarity, especially on instrumentally dense anthems like "Power to the People." I think you have to ask the intent of the remixes given what Paul Hicks had to work with. Surely there were compromises. Success should be based on intent, not an idealistic view of perfection. Now feel free to tell me I'm an a**hole.

 

[ssully]

I'll pop these posts of mine here from the other thread, though it concerns 7.1 as well as 5.1 .

If the 7.1 is a 'core' component in a Dolby Atmos file, is not the 5.1 also a core, for legacy purposes? That is, for hardware with pre-Atmos Dolby decoders?

[EDIT: this turns out to be not strictly true. The DD 5.1 is not an embedded core like a DTS core or DD 7.1 core of a TrueHD Atmos stream ; it is a separate bitstream that is defaulted to when the signal chain does not have an enabled TrueHD decoder)

We can extract and analyse cores without Atmos enabled using tools like MakeMKV. Would it be right to say that the only way to objectively analyse Dolby Atmos output in 7.1 (or 5.1?) with Atmos enabled (i.e., with extra channels mixed in to it) would be to record the analog output? Or is there any software yet that does Atmos decoding and can output in multiple channel formats? Because it looks like the comparisons people are interested in include

x.1 core vs x.1 Atmos-enabled
DD vs DTS

Could the DTS cores look so similar yet distinct from DD due to having had Atmos channels mixed in to the DD core before DTS encoding? IOW, the DD 5.1 core + Atmos channels folded in = DTS 5.1 ? This might make sense because you could not get the *Atmos-enabled* DD 5.1/7.1 experience from DTS without doing that .

It would require Atmos-savvy software tools to demonstrate, though.

and later,

If I understand correctly, then, a Dolby TrueHD stream (which can be up to 16 channels and is the bitstream by which Atmos is implemented) if played on a TrueHD capable and enabled system, can downmix from higher to lower channel output, including 5+.1+ >> 5.1. However if a 5.1 system lacks an enabled TrueHD decoder, it will play the separate, dedicated DD 5.1 bitstream.

But a TrueHD Atmos 7.1 file , played on a system with a TrueHD decoder but not Atmos configuration, plays the 7.1 'core' (in the case of Lennon here) of the Atmos bitstream with Atmos elements folded in. Is there any system configuration (e.g., Dolby PLIIz but not TrueHD) that would play the TrueHD 7.1 core without Atmos channel fold-in?

 

[harync]

This is the 7.1 TrueHD core for Instant Karma. FL, FR, FC obviously are problematic. What I can't understand is the Surrounds and Back. From what I understand of the mapping, the bottom two are the back while the two tracks above are the surrounds. Why such a big difference in amplitude there? Also note the big boosts during the chorus "And we all shine on..." It's the same as the DTS mix and there is no corresponding boost in the 5.1 DD mix.

As mentioned above, I don't think we can actually know what is happening with the Atmos mix without capturing line level outputs. However, I can't see how the Atmos version won't be similarly flawed.

 

[perzon57]

I have a 5.2 4 setup and it sounds balanced in the surrounds.Maybe someone with a 7.2.4 setup can chime in.

 

[musicmemorabiliashoppellc]

If anyone is having troubles not getting 5.1 or Atmos through their receivers.....read this article....it just might solve or at least tell you why you are having that problem.....you can thank me later

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[LuvMyQuad]

View attachment 58612
This is the 7.1 TrueHD core for Instant Karma. FL, FR, FC obviously are problematic. What I can't understand is the Surrounds and Back. From what I understand of the mapping, the bottom two are the back while the two tracks above are the surrounds. Why such a big difference in amplitude there? Also note the big boosts during the chorus "And we all shine on..." It's the same as the DTS mix and there is no corresponding boost in the 5.1 DD mix.

As mentioned above, I don't think we can actually know what is happening with the Atmos mix without capturing line level outputs. However, I can't see how the Atmos version won't be similarly flawed.

I believe you are correct. My take is this... The lower two traces are the surround rears. In a 5.1 system, they are the surround L/R. The two above it are the side surrounds in 7.1, and when the 7.1 is folded down to 5.1 they would be combined with the rear surrounds. I don't think anyone should get their panties in a twist about the level differences between the rears and sides. The mixer can use the area of the soundfield between the side and rear surrounds to cast an image just like he does with a stereo pair. In this case, the information given in the surrounds (both side and rear) looks like its tilted more toward the rear, so any "phantom center" type images would be biased in that direction, but probably more forward than would be the case with a 5.1 layout (assuming of course that the 5.1 mix didn't compensate for that by altering the image locations more toward the front L/R). If the amplitude of the rear and side surrounds were the same, images would seem to appear midway between them (again, assuming the side and rear carried the same info). It is certainly possible to include discrete information in the sides as well, should the mixer make that decision. The side surround output can also combine with the information coming from the fronts, as is common with 5.1 surrounds expanding the front image rearward. I don't have this release, so obviously I cant listen to it. But for all I know the sides may be producing some kind of ambiance effect, and the reduced level is as intended to produce the desired effect. There is no reason for all channels to have the same amplitude, whether 5.1, 7.1, Atmos, or even stereo. It all depends on what the mixer was trying to do.

The real issue here is the clipping. Atmos or no, nothing is going to restore that damage. Do you find the clipping audible? I'm pretty immune to compression effects unless its drastic. The Flaming Lips DVDAs are supposed to be an example of badly compressed sound, but I think they sound fairly good to be honest.

 

[jimfisheye]

It's like the channels in the 5/6 position didn't get the limiting and boost. Both the dts 5.1 and 7.1 atmos core files. The limiting and boost is about 2db less in the 7.1 vs the dts 5.1. The C and Lfe channels (position 3/4) appear to have gone through a stereo limiter as a pair FWIW. Then in the 7.1 file, channels 7/8 get limited and boosted but not as much as the 1st 4 channels. Obviously there's no position 7/8 in a 5.1 file.

Crude bs IMHO.

The raw mix escaping in the dd stream is clearly a raw mix with all the original headroom in place. The highest peak is -4.5db down. The whole thing could be boosted and limited +6db easily and there's be literally only a handful of isolated transparent peak reductions. This was clearly put into the dd stream instead of the mastered copy by mistake no matter what the opinion of the mastering is.

If this was mastered this way by request from the client... well, there ya go. I guess a few other people appreciate this a good 12db hotter than the raw mix and more front-centric too. (Based on the comments.) I prefer the raw mix significantly and my volume control is working for me.

PS. I don't think the distorted element comes from the peak limiting. There was mid scoop eq done and something else in the highs to make it sizzle. You can match the levels back to the raw mix but you can't undo the saturation distortion and make the fidelity match.

 

[ssully]

The real issue here is the clipping. Atmos or no, nothing is going to restore that damage. Do you find the clipping audible? I'm pretty immune to compression effects unless its drastic. The Flaming Lips DVDAs are supposed to be an example of badly compressed sound, but I think they sound fairly good to be honest.

True. I don't necessarily see 'clipping' there. Hitting 0dbFS by itself is not 'clipping'*. Nor do I see the front LRC as particularly 'problematic' in the 7.1 ; there is likely dynamic range reduction compared to the DD, but it's far from the most heinous I've ever seen on a surround disc. And even more compression doesn't necessarily mean bad sound (another example: Elton John 5.1 waveforms are pretty 'loud' -- but most people here like the sound of those, me included)

The 'issue' here for me is more the mystery of how and why these various renderings came to be.


*which is better thought of as a consecutive series of 0dBFS peaks or peaks at the same upper limit (e.g., if the audio was peak limited at 0 and then brought back down a little) - making a 'plateau' in the waveform. Those are more likely to be audible than single peaks that hit or exceed 0dBFS.

 

[ssully]

I'd like to see a recording of 5.1 line out playback on a TrueHD system (or software TrueHD/Atmos decoding to 5.1 wav file) . I hypothesize that it would resemble the DTS 5.1 rather than the DD 5.1 bitstream that is provided for legacy (non TrueHD) systems.

 

[b.smith]

Sorry if this is a dumb question but for me to hear the DD 5.1 I would have to:
1. Use an early AVR that pre dates Dolby TrueHD or
2. Rip the audio
I am not going to hear it using my Oppo 103 - correct?