Dolby vs. DTS mastering on same disc

[gorman]

I posted this in The Resistance thread but I guess it's relevant here as well.

https://tech.ebu.ch/docs/tech/tech3324.pdf

Page 25:

For example, consider Dolby Digital (DD) or DTS which have been in the market for more than 10 years: Dolby Digital requires 448 kbit/s and DTS still requires around 1.5 Mbit/s for "Excellent" quality. The newer codecs, such as Dolby Digital Plus or Windows Media provide "Excellent" quality only if operating at 448 kbit/s or above.
And this is the follow-up study: https://tech.ebu.ch/docs/tech/tech3339.pdf

Where, on page 20, you can check table n. 10, that shows how DD at 448kbps still produces good results. Note that this second study concentrated more on multiple transcoding scenarios, if I understand correctly, which are probably likely in a broadcast scenario.

So, basically, it's ok to use DTS 1.5 when available. But a better master in DD will most likely sound better than a worse master in DTS.

 

[jimfisheye]

I have the official Dolby media encoder software.
Dolby TrueHD is lossless. Nulls 100% with the multichannel wav source file.

I don't have the DTS encoder suite. I'm pretty sure it's safe to take their word that DTS-MA is lossless. Whole lotta people would have to be lying in cahoots for that not to be true anyway.

So the formats are lossless and the same source put to each would be bit for bit identical. The thing is that sometimes different masters are put to different formats! I've seen an example before where the lossless version of the program featured a blown out volume war style copy while the lowly lossy core Dolby version was an unmolested copy of the master. The intentional novelty destruction caused much more damage than the loss from lossy.

So formats aside, check out what might be hiding on those discs!

Dolby TrueHD+Atmos is in fact lossy though. Maybe that's what the claim above was aimed at? Not compression lossy... The difference audio in the metadata used to null the object channels back out of the bed isn't a straight phase translation like stereo <-> MS. It's more like a Fourier transformation based "center extraction". The mlp compression is lossless. The object extraction is not. I don't hear anything audible from this in A/B but it doesn't null.