Visual Impaired-Narrative

[cinefilm]

Hi All,
I did a 5.1 DCP with Track 7 (Video Description) and the same for track 8 (Video description). The assignment was track 7 = HI and track 8 = VI-N.
On the Dolby CP 750 (the setup is 7.1) there was no audio coming out of the "RCA" connector (HI and VI-N) but only on the Back Left Surround and Back Right Surround.
What I am missing?
Best regards

[carl]

Hi, do other HI/VI DCPs work on this system?

[Carsten]

The CP750 needs a very special setting for HI/VI in a 7.1 configuration. Up to the point maybe that 7.1 + HI/VI may not be possible with it.
I have to read it up in the manual again.
BTW - you can open the MXF audio track created by DOM in Audacity (with FFMPEG lib installed) directly and see wether everything is in place.

You also need to make sure the server uses the proper routing. This may be accomplished by software or in the AES cable from the server to the CP750.

edit: The CP750 only has an 8-channel digital input (4*AES on DB25) from the server. 7.1+HI/VI needs 10 input channels. The only way to accomplish this is to route 5.1 (1-6) and BsL/BsR (11/12) to this 4*AES input. That way, there is no connectivity left on this connector for the additional HI/VI channels. It is, however, possible to wire the HI/VI channels (7/8) to the digital In 2 BNC connector at the back with a special breakout cable. You can set the CP750 to 7.1+HI/VI mode with the setup application, given that the CP750 is also running on current software. Then the signal on Digital In2 is routed out of the Aux out 7 & 8 RCA jacks. Note there is a single dedicated HI/VI out connector on the back as well, but that always carries a mix of L/C/R, never any signal from the DCP HI/VI channels.

So, basically it depends on wether you are 'just' a filmmaker trying to play a 7.1+HI/VI track on this system, or - you are a projectionist being able to reconfigure the system or put some pressure on the owner/operator to do so.

The necessary information is contained in Dolby CP750 manual rev 5 and Dolby CP750 1.2.8.3 Release Notes.


- Carsten

[cinefilm]

Hi, do other HI/VI DCPs work on this system?

Thank you Carl
I don't know it is the first time.
Best regards

[cinefilm]

The CP750 needs a very special setting for HI/VI in a 7.1 configuration. Up to the point maybe that 7.1 + HI/VI may not be possible with it.
I have to read it up in the manual again.
BTW - you can open the MXF audio track created by DOM in Audacity (with FFMPEG lib installed) directly and see wether everything is in place.

You also need to make sure the server uses the proper routing. This may be accomplished by software or in the AES cable from the server to the CP750.

edit: The CP750 only has an 8-channel digital input (4*AES on DB25) from the server. 7.1+HI/VI needs 10 input channels. The only way to accomplish this is to route 5.1 (1-6) and BsL/BsR (11/12) to this 4*AES input. That way, there is no connectivity left on this connector for the additional HI/VI channels. It is, however, possible to wire the HI/VI channels (7/8) to the digital In 2 BNC connector at the back with a special breakout cable. You can set the CP750 to 7.1+HI/VI mode with the setup application, given that the CP750 is also running on current software. Then the signal on Digital In2 is routed out of the Aux out 7 & 8 RCA jacks. Note there is a single dedicated HI/VI out connector on the back as well, but that always carries a mix of L/C/R, never any signal from the DCP HI/VI channels.

So, basically it depends on wether you are 'just' a filmmaker trying to play a 7.1+HI/VI track on this system, or - you are a projectionist being able to reconfigure the system or put some pressure on the owner/operator to do so.

The necessary information is contained in Dolby CP750 manual rev 5 and Dolby CP750 1.2.8.3 Release Notes.


- Carsten

Thank You very much Carsten.
It's clear
Best regards