[Released] D-Theater audios

[Kameraposti]

Ninth.Gate.Bluray.synch

As the UHD release is getting closer...

Audio
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Duration : 2 h 13 min
Bit rate mode : Constant
Bit rate : 576 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Stream size : 550 MiB (100%)
Service kind : Complete Main
Dialog Normalization : -27 dB
Center mix level (cmixlev) : -3.0 dB
Surround mix level (surmixlev) : -3 dB
Dialogue normalization, average : -27 dB
Dialogue normalization, minimum : -27 dB
Dialogue normalization, maximum : -27 dB

DVHS capture had some faulty frames and those were replaced with Bluray audio

[Kameraposti]

The.Ring.synch.to.UHD.+876ms

Audio
Format : DTS
Format/Info : Digital Theater Systems
Duration : 1 h 55 min
Bit rate mode : Constant
Bit rate : 754 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossy
Stream size : 622 MiB (100%)

I know there is a Cinema DTS available. This lossy audio is just an alternative

[Kameraposti]

K-Pax

Audio
ID : 2
Format : DTS
Format/Info : Digital Theater Systems
Codec ID : A_DTS
Duration : 2 h 0 min
Bit rate mode : Constant
Bit rate : 754 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 16 bits
Compression mode : Lossy
Delay relative to video : 10 ms
Stream size : 649 MiB (3%)
Language : English
Default : Yes
Forced : No

[little-endian]

@Kameraposti: fantastic work, I also have a bunch of D-Theatre tapes, but still looking for a decent recorder and wanting HDMI AND DTS-output pretty much narrows it down.

Ninth.Gate.Bluray.synch

As the UHD release is getting closer...

Oh yes, very soon. Hopefully, they didn't mess with the image and just used the better source compared to the mediocre Blu-ray (which however is a pretty good "test" source for the LG G5 as it reveals all the issue that TV still has with SDR/lower light output content), making the source appear even grittier than it already is.

DVHS capture had some faulty frames and those were replaced with Bluray audio

Which is due to wear of the source tape I suposse? So the error correction is overstrained and each run at that particular position gives you different data?

I know there is a Cinema DTS available. This lossy audio is just an alternative

Mind you, that Cinema DTS is lossy as well. Still wondering which one is technically superior (APT-X100 vs. Coherent Acoustics), but subjectively, both are probably transparent for most content anyway.

[uVSthem]

Are any of the D-theater audios native 24bit 48.0 kHz? If they are, that would be would be an upgrade over the Cinema DTS discs since those are 16bit, 44.1hz, no?

[little-endian]

No, when talking about linear PCM on D-Theater tapes, it will be 48 kHz 16-Bit, not 24-Bit.

Also note that Cinema DTS isn't 16 Bit per se, but usually only decoded as such. Lossy codecs don't have that kind of immanent bit depth but may use lower precisions to store sample differences or floating point instead (like MP3, AC3, DTS, etc.). Interestingly, the dynamic range (usually at the cost of the SNR) can be higher than that of 16-Bit or even 24-Bit PCM (which is already insanely high and can't be used in real-life scenarios for audio anyway).

Technically (!), 16-Bit PCM would already be preferable to Cinema DTS, but I doubt that one will pass a blind test. Same goes for AC3 or DTS in most cases.

In short: all these formats are already "too good" to be the limited factor in practise, despite all the audiophile marketing, as to mask mixing and mastering differences so it is virtually entirely up to these two aspects to determine the quality.

Hence, one would have to compare the concrete mix of the D-Theater title in question and compare it to the Cinema DTS counterpart. Cinema DTS has - just like the optical Dolby Digital / AC3* track used on 35mm film back then - however the advantage of giving the psychological peace of mind that it was used in the cinema and thus acts like a reference.

* never came across those mixes though, would be an interesting project to preserve e.g. the AC3 of "Batman Begins" from 1992, encoded at allegedly even only 320 kbps (!) in the cinema

[Sambarker04]

No, when talking about linear PCM on D-Theater tapes, it will be 48 kHz 16-Bit, not 24-Bit.

Also note that Cinema DTS isn't 16 Bit per se, but usually only decoded as such. Lossy codecs don't have that kind of immanent bit depth but may use lower precisions to store sample differences or floating point instead (like MP3, AC3, DTS, etc.). Interestingly, the dynamic range (usually at the cost of the SNR) can be higher than that of 16-Bit or even 24-Bit PCM (which is already insanely high and can't be used in real-life scenarios for audio anyway).

Technically (!), 16-Bit PCM would already be preferable to Cinema DTS, but I doubt that one will pass a blind test. Same goes for AC3 or DTS in most cases.

In short: all these formats are already "too good" to be the limited factor in practise, despite all the audiophile marketing, as to mask mixing and mastering differences so it is virtually entirely up to these two aspects to determine the quality.

Hence, one would have to compare the concrete mix of the D-Theater title in question and compare it to the Cinema DTS counterpart. Cinema DTS has - just like the optical Dolby Digital / AC3* track used on 35mm film back then - however the advantage of giving the psychological peace of mind that it was used in the cinema and thus acts like a reference.

* never came across those mixes though, would be an interesting project to preserve e.g. the AC3 of "Batman Begins" from 1992, encoded at allegedly even only 320 kbps (!) in the cinema

I don’t think PCM can be possbile on a D-Theater tape. I know this because I found a D-VHS Telegram group which does direct transfers of the D-Theater tapes, and it turns out the PCM is just what was outputted on the optical out port. The stereo tracks are actually MPEG-2 Audio, meaning it would sound worse than AC-3.

[little-endian]

I don’t think PCM can be possbile on a D-Theater tape.

That, at least in general for DVHS is answered by the corresponding manuals, e.g. this one. Referring to page 87, it is clearly stated that LPCM audio is supported and possible (anything else would also be very odd, given how relatively new the format is and how common LPCM already was back then with DAT at latest).

I know this because I found a D-VHS Telegram group which does direct transfers of the D-Theater tapes, and it turns out the PCM is just what was outputted on the optical out port.

How concretely did that "turn out"? By what observation? The raw rip? Possible.

In fact, none of the back covers state PCM explicitly, but only "English(Stereo)", so it could also be something like MP2 to be used for that, especially when there were additional DTS tracks included, taking valuable resources as well. One would indeed have to check the raw rip of such a tape.

However, lddb.com in fact states PCM as well.

The stereo tracks are actually MPEG-2 Audio, meaning it would sound worse than AC-3.

Possibly, but not necessarily, since even when assuming AC3 to be more efficient, it would still depend on the concrete bitrates used.

As mentioned, this is a rather academic aspect anyway - when in doubt one wants to have the best mix whatever container that comes in.