This is topic Cinemark Policy, digital soundtracks on it in forum Film-Yak at Film-Tech Forum ARCHIVE.
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Posted by David Stambaugh (Member # 1102) on 02-11-2002, 05:51 PM:
This question pertains to Cinemark 17 in Springfield, OR. The current Cinemark policy seems to carry DTS timecode as well as Dolby SR-D (don't know about SDDS). Now being that I am observant about such things 
I've noticed that the DTS version of the policy consistently produces some very strong, deep LFE bass. You can clearly tell the .1 LFE channel is working. But when the policy is played in SR-D auditoriums, that deep bass seems to be missing. This behavior seems consistent in different auditoriums at the same location, depending on whether they are DTS or SR-D (they are all either one or the other; none have both). The features also seem to have much better LFE in the DTS houses than in the SR-D ones. Disregarding the subjective assessment of the LFE sound in the features (which change with every visit), the policy is the same every time and it seems like it should sound about the same in both formats. ?? Any ideas?------------------
- dave
I want that North American cable deal!
Posted by Joe Redifer (Member # 3) on 02-11-2002, 06:45 PM:
Maybe someone played with the subwoofer levels in the DTS houses or lowered them in the Dolby houses.
Posted by Bobby Henderson (Member # 840) on 02-11-2002, 06:46 PM:
The more enhanced bass in the DTS version could be coming from how DTS redirects sub bass info in the surround channels to the subwoofer (actually, this is where the LFE audio is stored, which really makes theatrical DTS a 5.0 format). Most movie theaters have surround array speakers of limited dynamic range. Most sub bass recorded into the surround channels will not be heard unless a crossover filter redirects the audio. Bass management in home theater uses this principal. Dolby Digital and SDDS have full range surround channels and the LFE channel is discrete. Perhaps Cinemark only mixed the audio in 5.0 with it tuned for DTS instead of making a full 5.1 mix.Previous 70mm formats like Format 43 used the method to literally stick two potential mixdowns on the same 6-track mix. Format 43 70mm prints all held backward compatible Format 42 mixes. The mono surround channel in Format 42 also held the sub-bass audio for Format 43. The two stereo surround channels in Format 43 held low bass audio for the two LFE channels in Format 42. The three front stage channels remained unchanged.
Posted by Brad Miller (Member # 2) on 02-11-2002, 06:57 PM:
It could also be the tech who installed the place. For some reason many techs seem to think the dts units are a direct plug in like a DA20 and frequently the pots are not exactly balanced or they fail to set the "digital subwoofer" input properly. Also, depending on the way the dts was wired in, the subwoofer could be running at a fixed level, although I doubt it since this sounds like a fairly recent complex.I can assure you though if the two formats were both balanced identically that the levels would be the same. Sounds like a bad sound tech or a tinkerer in the booth.
Also, can anyone from Cinemark deny or confirm if the dts audio is actually on the dts discs? I know UA made a policy trailer but the audio was never on any disc. You could be hearing analog.
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