DVD Audio Differences

[John_Smith]

When a DVD of the same title is released by different companies there's usually going to be differences between them with the picture quality, extras material etc..
What I've always wanted to know is could two of the same audio soundtracks on a DVD of the same title (for ex. a 5.1 DTS) released by different companies have differences in them ? Such as in volume leveling, bass level, bitrate etc.

[Samuel_Scott]

First off, welcome to the site John!

To answer your question simply, yes. Each company will author their disc differently and although most will come from the same source, the the bit rates will most certainly differ, even if ever so slightly. There has also been some instances where music is changed as licenses can't be granted in some localities, and even companies adding additional sound effects to up mixes. As we can't check every disc ourselves, we go on the basic paper specs for our comparisons, but some great places for reviews can be found via http://www.dvd-basen.dk

Other sites like the AV Forums and HTF often have some cracking stickied thread showing various bit rates etc.

EDIT: Bit rates even change between different localities even when releases are from the same major studios. This is more prevalent with HD releases than DVD though.

[Alister_Manson]

Often audio bitrates are the first thing to suffer if a DVD or BD has extra content or multiple language options. For a random example, Kill Bill Vol 1 and Vol 2 and the first three Pirates of the Carribean BD releases have 24-bit PCM audio on the US release and 16-bit on the non-US versions. Another similar example is that the US release of Troy has a PCM audio track, but the European releases have Dolby TrueHD to allow for more dubbed audio tracks, even though the film and extras are identical.

[John_Smith]

Among two different DVD distributors, how common is it for DTS tracks from the same title to have different bitrates ?

[Samuel_Scott]

For DVD, not too common. There are generally two standard bit rates used for DTS tracks on DVD which are often simply referred to as half bit rate (756kbps) and full bit rate (1536kbps). A standard Dolby Digital 5.1 track on DVD is 448kbps.

For Blu-ray, it would be a surprise if two companies had the same bit rate, unless the discs were direct ports of one another (ie. one company licensing another's release wholly).

EDIT: This part of Wikipedia will tell you more - https://en.wikipedia.org/wiki/DTS_(sound_system)#Comparison_with_other_formats

[Ulrich_Christensen]

A standard Dolby Digital 5.1 track on DVD is 448kbps.

It can also be 384kbps. I see this quite often. Especially I see it on DVDs with multiple audio tracks.
Sometimes dubs are 384kbps while the original audio is 448kbps. Other times all tracks are either exclusively 384kbps or exclusively 448kbps. Then there are those with the original and selected tracks in 448kbps and the rest in 384kbps. A few couple of times I have seen a dub in 448kbps with the original in 384kbps, but that seems to be an exception.