Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Datasat Digital Sound
#31
The cinema version of DTS-ES was not a separate format like the 6 and 8 channel variants were. DTS-ES was encoded into the standard 5 channel DTS APT-X100 format. It would have required an external decoder unit to decode the Center Back channel from the standard stereo surrounds, just like a matrixed 6.1 DTS-ES or Dolby Digital EX for home formats. This of course means that the surround channels encode 4 channels into two, three surround channels plus the LFE.

When working with DTS-ES cinema titles, the ideal would be to simply encode the finished audio as 5.1 with a matrixed center back channel, meaning either a matrixed 6.1 DTS-ES (or DTSHD-MA) or DDEX. Your AVR will decode the back center channel just like the cinema processor would.
Reply
Thanks given by: nafroe
#32
(2018-11-29, 08:59 PM)schorman Wrote: That may be a good thing, actually.  The two issues I ran into with decoding the DTS cinema discs were that the winamp decoder introduces audible artifacts in the Right and Right Surround channels.  The foobar decoder does not have this issue, and is therefore preferable.  However, the foobar decoder automatically separates the LFE and surround channels, but unfortunately the levels for those channels do not seem to be accurate.  For instance, DTS documents suggest that the surround channels should be attenuated by 3dB and the LFE track needs some amount of gain applied (The amount is dependent on when the film was released, and I'm not sure it's been established exactly how much should be applied).  The foobar decoder does not attenuate or apply gain to any of the channels, it just separates them by applying low and high pass filters.  As far as the crossover, I'll just say I'm not sure it's accurate to the DTS specs provided in their white paper.

Anyway, the newer decoder may allow us to avoid the audible glitches of the winamp decoder and still decode the LFE and surround channels in software, thus avoiding the potentially inaccurate low and high pass filtering being done by the older decoder.  As far as I'm aware, there's not a big need to use the decoder for real-time playback, so while it's nice to have the LFE and surround channels split, I'd rather do that in software for better results.

See this document here: http://www.film-tech.com/warehouse/manua...STPROD.pdf

"Subject: SMPTE RP200 changes DTS subwoofer level (REVISED) August 1999

At a SMPTE meeting held in late 1998, all three digital sound companies agreed to comply with the recommended practice for subwoofer level, SMPTE RP200. The subwoofer level has changed to enable the use of one master recording when transferring to all three digital sound processes and to provide playback consistency in theaters. As of January 1, 1999, the recorded subwoofer level on 6-track masters has been lowered to the SMPTE recommended level of 10dB in-band gain (as compared to the screen channels).


To comply with this new standard, all DTS films released in North America after January 1, 1999 have been transferred into the DTS digital process with subwoofer at 10dB in- band gain. The SMPTE RP200 logo is clearly visible on the discs of these films.


Because the recorded subwoofer level has been lowered, the DTS theater subwoofer playback should be increased. Increasing the DTS subwoofer level compensates for the new lowered recording level, resulting in the same playback as before the change.


To maintain the integrity of the cinema sound equipment, DTS discs of pre 1999 films should be played only after the subwoofer playback level has been restored to the previous 88 dBC level."


If my understanding is correct, subs should be set to 91dB for films released 1999 and onward, and 88dB for those released prior to this.  

BandD
Reply
Thanks given by:
#33
I'm pretty sure this was discussed before, can't remember if here or on OT.

The fact is: which level does the FooBar plugin produce?!?
Fundamental collection thread | Vimeo channel | My personal blog
Reply
Thanks given by:
#34
(2017-06-14, 04:58 PM)PDB Wrote:
(2017-06-13, 03:47 AM)Jetrell Fo Wrote: I would like to chime in and say that I have talked to one theater person I know and he said that the Datasat audio is encrypted and it isn't the same as the cinema DTS .aue file system so getting the audio and decrypting it are two totally different and difficult beasts at the moment.

Good to know, thanks for the info Jetrell. Did he say if they changed the file formatting too or just the encryption type?

(2017-06-13, 11:35 PM)CSchmidlapp Wrote: Great thread. Thanks guys.

'Dunkirk' is getting a 70mm and 35mm release, would this just be limited to the Dolby Digital mix then?
There is an ATMOS mix, but I gather no way to marry the two.

The 35mm would almost have to be DD, my Interstellar 35mm showing was and there is not much in the way of other choices. Not sure about the 70mm since Datasat said Hateful Eight was the last shipped disc. Someone could of taken that over I guess or maybe Datasat does one offs.

Maybe we should ask on the projector forum.

(2017-06-13, 11:56 PM)SilverWook Wrote: On a side note, has anyone ever figured out what sound system 70mm IMAX venues use? I've seen The Force Awakens and Rogue One at the IMAX dome in San Jose, (R1 had an extended Dunkirk trailer) but all the info graphics at the museum only cryptically refer to the soundtrack being on a CD.

Here you go:

http://in70mm.com/newsletter/1997/50/ima.../index.htm

It's all DTS CD
Reply
Thanks given by:


Possibly Related Threads...
Thread Author Replies Views Last Post
  Titanic (1997): Cinema DTS sound mix-Prepping for the Print…One Hopes. alexp120 29 8,699 2019-01-25, 04:57 PM
Last Post: Valeyard
  [Request] The Sound of Music NeonBible 0 353 2018-07-06, 05:08 PM
Last Post: NeonBible
  Dolby Digital Plus - any known preservations Bigrob 10 3,470 2017-06-13, 06:58 AM
Last Post: Chewtobacca
  DTS "Digital Experience" long version TServo2049 17 5,186 2017-01-23, 12:36 PM
Last Post: spoRv

Forum Jump:


Users browsing this thread: 1 Guest(s)