Does every BD disc have a core DTS and/or Dolby Digital audio track?

[Chordata]

Thanks.

If it's been done before I apologize.

[Hawk]

No. A good example is the new release of "Running Man." It contains only DTS-HD Master Audio 7.1. Not even a foreign language track.

[kpkelley]

Originally Posted by Hawk

No. A good example is the new release of "Running Man." It contains only DTS-HD Master Audio 7.1. Not even a foreign language track.

DTS-HD MA has a DTS Core track within itself.

[sptrout]

Originally Posted by kpkelley

DTS-HD MA has a DTS Core track within itself.

Agreed, all favors of DTS from standard DTS up to DTS-HD MA are backwards compatible with all DTS decoders thanks to the 1.5Mbps "core." Even very old AVR's that only have DTS via optical/coax will work fine if the DTS-HD MA track is selected. This is not the case with Dobly's TrueHD, which does require a separate lossy DD track to be backwards compatible with all older DD decoders.

[RBBrittain]

Originally Posted by kpkelley

DTS-HD MA has a DTS Core track within itself.

DTS-HD MA encoders do offer a "core-less" option, but it's almost never used; the studios have their encoders pre-configured to a full "core + extension" stream. They know anything less than a full stream weakens one of DTS-HD MA's greatest strengths--100% backwards & forwards audio compatibility, without going to the setup menu or writing complex scripts (the only ways to do it with LPCM or TrueHD).

And to answer the OP's question in a similar way: The primary audio track on a BD *may* be LPCM 2.0 as well as DD or DTS (including the "core" of DTS-HD MA). However, since all BD players are required to have DD & DTS decoders and nearly all of them have an optical or coax output as well, DD is most common (as with DVD--also, a few older, cheap HTIBs have only DD decoders though most now have DTS as well), with DTS close behind (especially on DTS-HD MA discs); LPCM 2.0 is rare.

[Uniquely]

My wife got me A Christmas Story... and it only had MONO AUDIO! Seriously. I can get at least 5.1 Dolby Digital on TBS..... but MONO AUDIO only on a Blu-ray? I was flabbergasted!

[un4gvn94538]

A few older discs back in the day only had pcm tracks if I recall

[WiWavelength]

Originally Posted by RBBrittain

DTS-HD MA encoders do offer a "core-less" option, but it's almost never used; the studios have their encoders pre-configured to a full "core + extension" stream. They know anything less than a full stream weakens one of DTS-HD MA's greatest strengths--100% backwards & forwards audio compatibility, without going to the setup menu or writing complex scripts (the only ways to do it with LPCM or TrueHD).

The following are the four most common BD lossless audio plus lossy fallback (English language) configurations:

Multichannel LPCM & Dolby Digital
DTS-HD Master Audio (with core DTS)
Dolby TrueHD (with embedded Dolby Digital)
Dolby TrueHD (with embedded Dolby Digital) & Dolby Digital

The most interesting aspect of the last configuration (utilized on many Warner BDs) is that it contains two Dolby Digital tracks. One is embedded in the Dolby TrueHD stream; the other is a separate, menu selectable Dolby Digital track. The two Dolby Digital tracks do not have to be identical (e.g. bit rate), but they potentially are.

AJ

[sihida]

(I can't create new threads in this forum, so I post in this topic.)

I'm a little bit confused about this:

If I'm correct, the blu-ray spec requires that a separate AC3 audiotrack must be present on blu-ray discs that contain a TrueHD track, because TrueHD is optional. But some recent blu-ray titles contain only a (English) TrueHD track with an embedded (not "completely" separate) AC3 track. Wouldn't this mean that some old blu-ray players with no support for TrueHD, can't play any (English) audio at all? Or are all blu-ray players able to extract the embedded AC3 track from the TrueHD one?

By the way, what's the whole point of using embedded AC3 tracks instead of separate ones? To output the "same" track (AC3 "version") over optical/coaxial S/Pdif as over HDMI (TrueHD "version")?

And what's the point of having an embedded AC3 track *and* a separate (duplicate) one (common on a lot of blu-rays)?

[BIslander]

Dolby and DTS took different approaches for handling lossless along with backwards compatibility for older technologies. The DTS approach is a lossy DTS core with extensions that contain the data for lossless Master Audio. The Dolby approach is a lossless TrueHD encode and a separate, companion DD 5.1 track. The DTS approach takes more processing power, which is why it was later into the market and why some processors can't decode dts-MA and apply DSPs for room correction and channel expansion. Nonetheless, both approaches work to provide lossless along with lossy versions that get used, as needed, without any end user intervention. If you play a dts-MA or TrueHD track, the software makes sure the output over optical will be DTS or DD 5.1 because that's all the S/PDIF protocol can handle.

In the early days, before lossless was possible, Blu-rays had PCM and DD 5.1 tracks. For awhile, Warner Bros. used TrueHD and included a separate, visible DD 5.1 track, which was set as the default. That was a pain for people with lossless capability because they had to select the TrueHD track after the disc started playing. Fortunately, that practice has stopped. These days, it is rare to find a disc that has more than one English language track. You get dts-MA most of the time and TrueHD occasionally. Music discs will often have a PCM option as well - either stereo or multichannel. But, that almost never happens with movies.

[BIslander]

Originally Posted by sihida

I'm a little bit confused about this:

If I'm correct, the blu-ray spec requires that a separate AC3 audiotrack must be present on blu-ray discs that contain a TrueHD track, because TrueHD is optional. But some recent blu-ray titles contain only a (English) TrueHD track with an embedded (not "completely" separate) AC3 track. Wouldn't this mean that some old blu-ray players with no support for TrueHD, can't play any (English) audio at all? Or are all blu-ray players able to extract the embedded AC3 track from the TrueHD one?

The spec does not require a separate DD 5.1 track. It requires players be able to handle DTS, DD, and PCM while discs only have to have one of them. The studios have found ways to make sure that audio on a disc with dts-MA or TrueHD can be fed to older equipment that lacks lossless capability.

By the way, what's the whole point of using embedded AC3 tracks instead of separate ones? To output the "same" track (AC3 "version") over optical/coaxial S/Pdif as over HDMI (TrueHD "version")?

It's simply the approach Dolby took for transparent backwards compatibility.

And what's the point of having an embedded AC3 track *and* a separate (duplicate) one (common on a lot of blu-rays)?

It was done by Warners, a practice that has since stopped. It was never common and I don't recall seeing it on any new discs since the Warner change. I gather they decided it was pointless, too.

[sihida]

Thanks for your answer.

Originally Posted by BIslander

The spec does not require a separate DD 5.1 track. It requires players be able to handle DTS, DD, and PCM while discs only have to have one of them. The studios have found ways to make sure that audio on a disc with dts-MA or TrueHD can be fed to older equipment that lacks lossless capability.

But what ways?

I know some (old) media streamers (like AC Ryan's first Playon!HD) can't handle TrueHD tracks and can't use/extract the embedded AC3 track; you get an 'unsupported audio codec' error and no sound at all on HDMI or S/Pdif. Can't something similar happen on (old) blu-ray players with no support (at all) for TrueHD?

[BIslander]

What ways? The DTS core and embedded DD 5.1 approaches described previously.

And sure, there may be some old, out of spec equipment floating around. But players built to spec handle backwards compatibility just fine.