Is Dolby TrueHD compatible with regular Dolby 5.1?

[Zeak]

Would it just decode as regular 5.1 like dts does?

[hardcorefrokid]

Don't understand the question. Like how DTS-HD Master Audio has a core DTS track. Are you wondering if Dolby TrueHD has a Dolby Digital track?

[Zeak]

if dolby truehd has a core dolby digital 5.1 track

[singhcr]

Originally Posted by Zeak

if dolby truehd has a core dolby digital 5.1 track

It does.

[randy8118]

Originally Posted by hardcorefrokid

01100011011000010110111000100000011110010110111101 11010100100000011100100110010101100001011001000010 00000110001001101001011011100110000101110010011110 0100111111

Your ones and zeros are razor sharp, you must be using a high quality HDMI cable.

[sptrout]

Originally Posted by singhcr

It does.

Not really. If an AVR (or player) cannot decode TrueHD then the decoder reverts to a separate standard DD track (640kbps). This is different than DTS-HD MA, which does have a 1.5Mbps "core" that can be read by older DTS decoders.

[krylonman]

Originally Posted by sptrout

Not really. If an AVR (or player) cannot decode TrueHD then the decoder reverts to a separate standard DD track (640kbps). This is different than DTS-HD MA, which does have a 1.5Mbps "core" that can be read by older DTS decoders.

Yep, that's it. Technically the answer is "no," but any TrueHD disc will have a Dolby Digital track to use for systems that can't decode it.

[statikcat]

Originally Posted by krylonman

Yep, that's it. Technically the answer is "no," but any TrueHD disc will have a Dolby Digital track to use for systems that can't decode it.

Is it stored as it's own ac3 file on the disc? Or is it encoded into the HD track somehow? I am not real clear and curious.

[steve_dave]

Originally Posted by statikcat

Is it stored as it's own ac3 file on the disc? Or is it encoded into the HD track somehow? I am not real clear and curious.

Its a seperate track from the Dolby TrueHD. Generally, this DD 5.1 track is hidden, meaning not selectable from the menu. Its up to the player to automatically select the proper track. However, some companies like Warner do allow you to choose the DD 5.1 track just in case the player can not choose properly.

The only issue is that Warner defaults everytime to the DD 5.1 track, you have to manually choose TrueHD from the pop-up menu.

[statikcat]

Originally Posted by steve_dave

Its a seperate track from the Dolby TrueHD. Generally, this DD 5.1 track is hidden, meaning not selectable from the menu. Its up to the player to automatically select the proper track. However, some companies like Warner do allow you to choose the DD 5.1 track just in case the player can not choose properly.

The only issue is that Warner defaults everytime to the DD 5.1 track, you have to manually choose TrueHD from the pop-up menu.

Good to know. I have noticed a few times I was playing DD 5.1 and had to switch it to TrueHD or HDMA. Now I know why.. Warner lol.

[krylonman]

Yeah, I think they're big into making their movies "idiot proof" (DVDs too); defaulting to the lossy soundtrack seems to come from the same mindset that has the movie start right up without a menu. It's annoying, but I guess it's better than a release of theirs running into a weird BD player that ends up just playing the movie with no sound, causing many returns from people who can't figure out that there isn't actually a defect.

[reece]

Originally Posted by sptrout

Not really. If an AVR (or player) cannot decode TrueHD then the decoder reverts to a separate standard DD track (640kbps). This is different than DTS-HD MA, which does have a 1.5Mbps "core" that can be read by older DTS decoders.

So what you're saying is that older recievers can still take advantage of DTS-MA, even without proper decoding? This would make sense seeing as some DTS-MA tracks (such as Wall-e) sound amazing on my older reciever, but I never really notice a difference with the DolbytruHD tracks...

[Russell_L]

Originally Posted by reece

So what you're saying is that older recievers can still take advantage of DTS-MA, even without proper decoding? This would make sense seeing as some DTS-MA tracks (such as Wall-e) sound amazing on my older reciever, but I never really notice a difference with the DolbytruHD tracks...

Well, not really. The receiver is reading the "core" track of DTS-MA, which means that it's decoding (and you're hearing) plain ol' DTS (without the extra resolution of the "MA" part).

[aramis109]

Originally Posted by Russell_L

Well, not really. The receiver is reading the "core" track of DTS-MA, which means that it's decoding (and you're hearing) plain ol' DTS (without the extra resolution of the "MA" part).

"Plain old DTS" ... well, sort of. It's still a higher-bitrate DTS (1.5mbps) than what's on DVD.

[reece]

Originally Posted by aramis109

"Plain old DTS" ... well, sort of. It's still a higher-bitrate DTS (1.5mbps) than what's on DVD.

ok so it is slightly better then. thats good to know. I'll tell you...if the goal with high def audio was to confuse people...it certainly worked on me

[odin24]

Originally Posted by steve_dave

Its a seperate track from the Dolby TrueHD. Generally, this DD 5.1 track is hidden, meaning not selectable from the menu. Its up to the player to automatically select the proper track. However, some companies like Warner do allow you to choose the DD 5.1 track just in case the player can not choose properly.

The only issue is that Warner defaults everytime to the DD 5.1 track, you have to manually choose TrueHD from the pop-up menu.

For Blu-ray this is not true. All BD TrueHD tracks have an AC3 track embedded in the in the TrueHD track... However some companies do offer a separate AC3 option... like Warner. If you attempt to send a TrueHD track through an optical cable you will get embedded AC3 file. If this is your setup, the next BD with TrueHD, select it and you'll still get DD 5.1... just not TrueHD.

Regarding hidden DD 5.1 tracks... absolutely not true, if it exists on the disc there will be an option to select it.

HDDVD TrueHD tracks on the other hand are slightly different, they do not have an AC3 track embedded, so there will be a separate AC3 trakc available... most likely a DD+ (E-AC3) track.

[BIslander]

Originally Posted by odin24

Regarding hidden DD 5.1 tracks... absolutely not true, if it exists on the disc there will be an option to select it.

I think this is a semantics issue. Unlike DTS, where the lossless track is constructed using the lossy core, Dolby uses two separate tracks. As you noted, the DD 5.1 track is embedded in the TrueHD package. That's why it is often called a hidden track. It's there, but can't be selected from the audio menu. Some studios such as Warners include a selectable DD 5.1 track on their TrueHD discs, although I don't know whether that's simply a visible link to the embedded track or a separate version.

HDDVD TrueHD tracks on the other hand are slightly different, they do not have an AC3 track embedded, so there will be a separate AC3 trakc available... most likely a DD+ (E-AC3) track.

HD DVD players also transcode TrueHD or DD+ to DD 5.1 or DTS on the fly. As best I recall, the HD DVD spec has a 448 kbps bitrate limit for DD 5.1, the same as DVD. That's what you get when you play the DD 5.1 track. But, transcoding allows for a 640kbps DD 5.1 output.

[BIslander]

Originally Posted by reece

So what you're saying is that older recievers can still take advantage of DTS-MA, even without proper decoding? This would make sense seeing as some DTS-MA tracks (such as Wall-e) sound amazing on my older reciever, but I never really notice a difference with the DolbytruHD tracks...

Originally Posted by reece

ok so it is slightly better then. thats good to know. I'll tell you...if the goal with high def audio was to confuse people...it certainly worked on me

There are those who say these higher bitrate versions of DTS and DD 5.1 on Blu-ray sound just as good as lossless much of the time. There are lots of variables that affect audio quality and I think you really need to try them out yourself on your equipment, in your room.

[Cinema Squid]

Originally Posted by BIslander

I think this is a semantics issue. Unlike DTS, where the lossless track is constructed using the lossy core, Dolby uses two separate tracks. As you noted, the DD 5.1 track is embedded in the TrueHD package. That's why it is often called a hidden track. It's there, but can't be selected from the audio menu. Some studios such as Warners include a selectable DD 5.1 track on their TrueHD discs, although I don't know whether that's simply a visible link to the embedded track or a separate version.

You're right about it being a somewhat contentious semantics issue. There is always a standard Dolby Digital track embedded within each TrueHD track on Blu-ray (interleaved with the same stream PID), but it does not form part of the lossless TrueHD data thus is not a "core" track as is the case with DTS-HD. The separately selectable Dolby Digital track provided by studios like Warner (and Weinstein) is physically separate from the standard embedded AC3 stream and, in most cases, is essentially a duplicate redundant copy of the AC3 stream embedded in the TrueHD track.