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GeekNews
07-26-2011, 06:53 PM
All

Running into a weird problem and the folks at BlackMagic are trying to help me work through this.

Their H.264 Pro recorder which takes an SDI input and then captures to .mp4 is fine but when we pull the .mp4 into Final Cut to edit the file we are hearing and Audio popping sound periodically through the track.

The audio is not being over driven or nothing like that but the BlackMagic folks are asking me if I have any clue as to the audio standard being sent on the SDI signal..

I expect it should be pretty standard but is their an actual audio out spec that is embeded in the SDI signal the tricaster provides?

Todd..

Will Waters
07-27-2011, 07:00 AM
Hi Todd,

Which model TriCaster are you using?

Please make sure you are on the latest software updates. You can find this out by clicking on "About" on the Home screen of the TriCaster, then "Check for Updates"

As far as your question about audio standard on the TriCaster, this is a difficult question to answer since there is no official standard for digital audio. Most professionals agree on referencing +4dBU to -20dBFS for professional applications. This is the scale that the TriCaster uses to output digitial audio.

GeekNews
07-27-2011, 05:55 PM
I have the 850 with the latest version.

One thing we noticed as an aside is that the audio levels are pretty low as compared to tricaster master recordings.

We did some more experimentation and it appears this is going to be a Final Cut issue as the audio popping did not carry over into Adobe Premier on the same recorded mp4 file that the blackmagic H.264 recorder captured.

What really pisses me off, is that everything I do to try and make a video work flow through final cut work and not take 10 F^&*(( steps is impossible.

The tricaster batch encoder is so slow i get more entertainment out of watching cloths dry. Even sucking the native .mpg into premier you have to wait for premier to do its magic on the file..

Great live product but crappy video output formats that slow down post production.

GaryG
07-28-2011, 02:24 PM
I have the 850 with the latest version.

One thing we noticed as an aside is that the audio levels are pretty low as compared to tricaster master recordings.


The levels from input to DDR to output on the TXD models are.. weird. It appears that a pad was added to the output stage in order to bring the XLR jacks to some voltage reference at 0db on the internal meters; the result being, from what I can tell, that you lose 14db from SDI input to SDI output through the machine.

I keep meaning to test this.

GeekNews
07-28-2011, 07:46 PM
Hmmmm

Are their any inline audio boosters for SDI?

Todd..



The levels from input to DDR to output on the TXD models are.. weird. It appears that a pad was added to the output stage in order to bring the XLR jacks to some voltage reference at 0db on the internal meters; the result being, from what I can tell, that you lose 14db from SDI input to SDI output through the machine.

I keep meaning to test this.