This is topic CP650 problem with DTS/Dolby-SR in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.
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Posted by Hugo Ruiter (Member # 3110) on 07-12-2005, 02:49 AM:
We have got the CP650 and sometimes when we are using DTS it's switching to Dolby-SR. Why isn't it switching to Dolby Digital?
If it's on Dolby-SR there is no sound on the left front speaker. If we are doing a bypass then there is sound on the left. Also if it's on DTS or Dolby Digital.
I think it's got something to do with the CP650 but i can't find anything.
I'm also searching for the software that if we connect a computer with the CP650 we can change things. Where can i find the software?
Hugo
Posted by Michael Schaffer (Member # 1204) on 07-12-2005, 03:53 AM:
When the DTS drops out of digital, it gives a pulse on the automation input of the CP650 (a pulse means a momentary dry contact closure, a dry contact is a contact with no or very low voltage (according to Dolby specifications lower than 2.4VDC), what in German is called "potentialfrei", it's probably very similar in Dutch). The DTS is normally configured to pulse on pin 3 which selects SR. You can try this yourself when you create a momentary conductive (i.e., a wire) connection between pin 12 (GND) and 3. Pin 4 selects Dolby Digital.
How does your projector automation communicate with the CP? Is it connected to the automation connector, or to the serial input? If it is connected to the analog automation input, your DTS will be connected to a breakout board sitting on the auto input to provide dual inputs for automation and DTS.
Which one is it? Is it D715? If so, what I would propose is this. I am saying propose because I have thought about trying it myself, but haven't the opportunity yet. If I am missing something or there is an error here, I am sure it will be pointed out by other posters soon:
Snip off the pin which inputs the pulse on pin 3 on the male connector of the board and then solder a jumper on the other side of the board from 3 to 4. The DTS will still pulse on 3, but the pulse will be directed to 4.
AFAIK, there is no way to change the pulse config of the DTS to pulse on 4. You have to observe that there is a jumper on the board which defines if SR is on pin 2 or 3. Since your systems goes to SR, that jumper is obviously set correctly.
For the other problem, you first have to check if the solar cell reads both channels and if the analog Dolby level is set correctly. How to do this is described in all detail in the manual.
Since the software is not posted here, I do not know if Dolby doesn't want it to be posted. Brad is the man to ask about that.
And as always, please only make config changes if you are allowed to by your employer.
Posted by Peter John Anthony. C (Member # 2500) on 07-12-2005, 10:31 AM:
Snip off the pin which inputs the pulse on pin 3 on the male connector of the board and then solder a jumper on the other side of the board from 3 to 4. The DTS will still pulse on 3, but the pulse will be directed to 4.
Dear Michael that was a good idea, but what if the next fim comes with only DTS timecode & SR sound track no Dolby Digital??
The only thing is come back to square 1 ( how it was before)....right please correct me if i am wrong..
Thanks
Posted by Scott Norwood (Member # 30) on 07-12-2005, 10:51 AM:
Not a major problem. If the DTS unit faults to format 10 and there is no SRD track, then the CP650 will revert to 05 (SR). This might be a problem with early DTS releases with "DTS Stereo" optical tracks (which use A-type NR and would sound bad if played in SR), but how often does DTS fault, anyway?
I suppose if it's really an issue, one could configure DTS to fault to one of the user-defined formats and set that format up as SRD, to be changed only if the optical track on the print is A type.
Posted by Peter John Anthony. C (Member # 2500) on 07-12-2005, 11:10 AM:
Yes Scott you were right.
Thanks.
Posted by Michael Schaffer (Member # 1204) on 07-12-2005, 06:02 PM:
It's even easier: assuming you have the D715 board, simply move the jumper on the board which defines where SR is located from "SK3" to "SK2". Then it will pulse to A-type even when it means to pulse to SR. Assuming you have a CP650 where you can not relocate formats. With the CP500, you don't have these problems: you can assign whatever you want to whatever SK. I used to drop the A-type from SK2 and doubled Dolby Digital there, then moved the SR jumper from the SK3 position to SK2. When reverting, the DTS-6D would pulse on SK2 "thinking" it was telling the Cp500 to go to an SR format. But it would actually find DD there, and everything was fine.
The information about whether the optical track is A or SR is actually programmed on the disc. But if that programming is wrong, or you want to force the unit to fall back to A instead of SR (for whatever reason), moving the jumper will do the trick. If there is a Dolby Digital track as well, the optical track is always SR anyway.
This is all with DTS-6D and D715 as examples. Things are a little different with other processors and boards, but the principles are of course exactly the same.
Posted by System Notices (Member # 2357) on 09-23-2007, 05:47 PM:
It has been 802 days since the last post.