Trying to figure out lossy and lossless versions

[fthesoundguy]

Hey all,

Another newish question, this time its with all of the different versions that come on these discs and trying to make sense of it all. Let me just jot some stuff down and tell me if I’m wrong.

Lossy:
Dolby Digital: 640 kbps for Blu Ray Players or 448 for DVD players. Is this why the Pink Floyd Immersion sets had those two different streams on the disc?
DTS: 1.5 Mbps for BR or 768 kbps for DVD.
Are both of these 16 or 24 bit? It also looks like the sample rate would be 48k for both.

DTS 96/24: This seems like it uses the core DTS stream and then adds on a little bit of compressed information to get it up to 96/24 theoretically. Am I right on that? So its a little better than regular DTS, but still not great.

Dolby Digital Plus: 1.7 Mbps
DTS-HD High Resolution: 6 Mbps
Were there many music discs that utilized this quality? It looks like the DTS version is comprised of the core DTS with two extensions to bring it up fully to 24/96k. Same with DD+ with a 640kbps core and a 1Mbps extension.

Lossless:
PCM/DSD: Totally uncompressed
Dolby TrueHD - 18 Mbps
DTS-HD MA: 24.5 Mbps
Looks like both the DTS and Dolby do the standard stream with even further extensions.

So in theory, its better to always use the LPCM option if you have it and then go to the DTS than Dolby versions?

Also, if my AVR doesn’t have the lossless Dolby/DTS options (My Yamaha RX-V2600 only has regular DD, DTS and DTS 96/24) Does that mean that any disc which has a DTS-HD MA stream just gets the DTS core audio of 16 bit (or is it 24?)/ 48k? And if it happens to also have a DTS 96/24 stream (The Rush AFTK BD-A does) then I get that additive info to make it a little better?

And if I have the option between LPCM and DTS-HD MA, for right now, I should always go LPCM because i’ll get the full lossless stream?

Also, I’ve seen AC-3 and MLP floating around in some of the messages. What are these? Is AC-3 just another name for Dolby? And MLP seems like its the PCM compression technique for DVD-A discs. Would this mean if a title was released on BD-A and DVD-A, the DVD-A would be compressed with MLP while the BD-A is fully uncompressed PCM files?

I didn’t get into Atmos / DTS:X because I am not even in the realm of upgrading my system (mainly just my AVR at this point) to get a full rig going. It seems like things are getting mixed in Atmos but DTS:X is getting left in the dark (As far as music is concerned).

 

[MCDave]

So in theory, its better to always use the LPCM option if you have it and then go to the DTS than Dolby versions?

In theory, LPCM should sound the same as any of the lossless options, because that's what "lossless" refers to. The lossless encoding just takes the LPCM data and packages it up in a wrapper. Your processor or AVR (if equipped) will display the name of the wrapper on its front display so that you know what you're hearing, but as far as quality of sound, nothing should beat LPCM because it's the LPCM data that gets "unwrapped" and converted to analog. So why even provide these lossless options at all, if they sound the same as LPCM? Because they were developed for movie soundtrack playback, and video takes up a lot of space on the disc. Lossless (and lossy) compression algorithms were developed so the soundtrack could be compressed on the disc to make room for more video.

Also, if my AVR doesn’t have the lossless Dolby/DTS options (My Yamaha RX-V2600 only has regular DD, DTS and DTS 96/24) Does that mean that any disc which has a DTS-HD MA stream just gets the DTS core audio of 16 bit (or is it 24?)/ 48k? And if it happens to also have a DTS 96/24 stream (The Rush AFTK BD-A does) then I get that additive info to make it a little better?

Yes, the extra information contained in a lossless codec will be stripped if your processor isn't capable of decoding it, and you'll just hear the core soundtrack. Note that for blu-ray and dvd-audio the LPCM standard is 96kHz/24-bit for 5.1, and either 24/96 or up to 24/192 for stereo. Core DTS and DD are 24/48.

And if I have the option between LPCM and DTS-HD MA, for right now, I should always go LPCM because i’ll get the full lossless stream?

Again, theoretically they should sound the same. Some people claim that LPCM sounds better, but I think they're imagining it. There may be a level difference that accounts for a preference for one over the other in a listening test, but the lossless codecs are quite good at being doing their job.

Also, I’ve seen AC-3 and MLP floating around in some of the messages. What are these? Is AC-3 just another name for Dolby? And MLP seems like its the PCM compression technique for DVD-A discs. Would this mean if a title was released on BD-A and DVD-A, the DVD-A would be compressed with MLP while the BD-A is fully uncompressed PCM files?

AC-3 = DD. Both the DVD-A and BD-A would have 24/96 LPCM in multichannel, although you may not be able to select the LPCM playback on all discs. The only differences would be what bitstreams are available to select from the menu.

I didn’t get into Atmos / DTS:X because I am not even in the realm of upgrading my system (mainly just my AVR at this point) to get a full rig going. It seems like things are getting mixed in Atmos but DTS:X is getting left in the dark (As far as music is concerned).

[/QUOTE]

Yep, Atmos is winning the format war with DTS:X.