DCP AUDIO LEVEL

Anything and everything to do with DCP-o-matic.
Carsten
Posts: 1888
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: DCP AUDIO LEVEL

Post by Carsten »

As I suspected. Did you make a note what type of processor they use? Because, 85dB is common only at 7 - below 7, the various cinemaprocessors use different attentuation curves. Depending on the type of processor, 5 could mean between -7dB (Dolby) and -10dB (Datasat/USL)

So, did they say that their normal feature level is 5? Some people would say - '7 is the standard, so it should be right!'
But, as matter of fact, no cinema plays features at 7.



One problem is - your peak level in Ls and Rs is already quite high - look at the end of the chorale part.
As I wrote above - you may need to reduce Ls and Rs by e.g. 6dB in order to gain enough headroom for a global gain adjustment. Otherwise, you may only increase overall volume by around 5dB before you run into clipping in Ls and Rs. I think +5dB global gain is not enough. That based on the assumption that the chorale passage has the highest peak levels in the whole piece. Can you show us a screenshot of the audio analysis for the whole piece?
Richardfox
Posts: 9
Joined: Thu Apr 15, 2021 3:08 am

Re: DCP AUDIO LEVEL

Post by Richardfox »

Question on Audio Levels. So I successfully made the dcp using dcpomatic and again successfully tested it in an actual cinema. Picture and audio were PERFECT; however, I came back and exported a ProRes version of the same dcp and I could hardly hear anything without a headphone. Can anyone say what might be the issue? I now need to send a file for possible streaming opportunity.

Thanks!
Carsten
Posts: 1888
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: DCP AUDIO LEVEL

Post by Carsten »

You have a choice of exporting stereo/downmix or multichannel. What did you use?


You could also just create a new DCP-o-matic project and reimport that ProRes file, then check levels again.


Which version of DCP-o-matic did you use?

Basically, levels should remain unaltered for export.

Just doing a trailer export with 2.14.48 for a test...

Looks okay for me:

Bildschirmfoto 2021-04-15 um 10.59.10.png
Bildschirmfoto 2021-04-15 um 10.59.10.png (151.25 KiB) Viewed 1377 times
Bildschirmfoto 2021-04-15 um 10.59.43.png
Bildschirmfoto 2021-04-15 um 10.59.43.png (144.99 KiB) Viewed 1377 times
Wondering what happened in your case.
zsantiz
Posts: 2
Joined: Thu Nov 25, 2021 6:10 pm

Re: DCP AUDIO LEVEL

Post by zsantiz »

Hi Carsten, first I apologize for my English, I am using google translator.

DCP Magic warns me for a -1dB pick, like the warnings I see in your image. Should I be concerned about that? Thank you!
Carsten
Posts: 1888
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: DCP AUDIO LEVEL

Post by Carsten »

No. Peak is only an issue if you actually hit 0dB True Peak. Peak and True Peak are strict technical problem indicators - when you hit 0dB, signal may clip and distort. RMS/LEQ/LUFS on the other side are perceptual warning indicators. If these are too high, audio may be considered too loud, but it is not a strict technical problem as clipping is.


- Carsten
zsantiz
Posts: 2
Joined: Thu Nov 25, 2021 6:10 pm

Re: DCP AUDIO LEVEL

Post by zsantiz »

Very clear. Thank you!
Post Reply