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I needed the D.T.S. level and switch information, but due to restricted computer access (cable problems) decided to try for a quick answer. As the cable connection became stable again, i looked up my original post from 3 years ago, under the topic "Digital Poll "which follows:

From 04 Sept. 99

Joe, I wonder if you are using different tracks for setting the auditoriun S.P.L. than I am, and why the lower volume in centre channel.
I have been using;
37 - Left channel 85 dB(c)
38 - Left surround 82 dB(c)
39 - Centre channel 85 dB(c)
40 - Right surround 82 dB(c)
41 - Right channel 85 dB(c)
42 - Subwoofer 91 dB(c)
I turning off the subwoofer amp when setting
the surrounds, and vice-versa.
From memory, the delay is set by counting the frames from the reader pick-off to the aperture and multiplying by 1.25 (the D.T.S. time-code being based on 30 frames/sec).
If anyone is considering making their digital systems truly portable, may I suggest looking into the Kelmar "docker" system. Properly set up, changing heads is a snap, and time delays are the same for all booths. (If different projectors are used, the delay is set for the longest projector, and spacers are used to compensate).
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Using a current DTS setup disk you should playback the 1kHz tone and adjust all output potentiometers so that you can measure 300mV (AC) from each of the 6 channels.

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I don't know if it would make a difference if you were connected (I'll let someone else answer that) but that's probably not how they intend for you to make these settings.

BTW, I learned this information right here at Film-Tech.com earlier this year.

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Also, the subwoofer level really can't be set properly without an RTA as compared against the stage speaker's low frequencies. The sub should have a 10db in band gain over the stage channels.

You will also find setting each surround to 82 1/2db @ C weighting is more accurate of a setting to achieve a sum of 85db. Of course this requires an analog SPL meter, but here again this just goes to show how superior analog can be to digital.

(Apologies to Darryl)

Rick

I found the 300mV procedure very accurate. The level between Dolby Digital and DTS is the same if you set the DTS levels at 300mV.

I'm confused about the SPL levels. Let's ignore the Subwoofer level (that requires an RTA). Our tech set the microphone, EQ all the channels, and then set the levels. He set in the same day both DD and DTS levels, without moving the microphones and using the same RTA (R2 THX).
Then I checked the levels with my tester: 380mV the stage channels, 300mV the rear channels. How is it possibile? I personally saw the SPL readings on the R2 (85-82 dB).

More: just for fun I tried my own RTA (a cheap measurement microphone with Spectra LAB). The curve was not accurate, perhaps becasue I have just one microphone. But when I checked the levels I saw that, at 300mV, DTS pink noise is lower than DD one on RTA (5/6 dB), and the SPL reading was lower.

Any explanations?

That above sounds to me like the individual engineers suggestion not Cinemark as a whole since I have not seen or herd about any such settings.

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