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EBU colour bars and tone for PAL


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#1 zook

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Posted 21 October 2009 - 12:39 PM

I've been asked send some work I've created directly to a broadcaster and amongst the specs is the following sentence:

"5 seconds of EBU colour bars (100.0.75.0) and accompanying 0dBm (-18dBfs) stereo identified audio tone @ 1 KHz
sine."

I've found some tone bars on the internet, but have no idea what this tone is. Does a sound file exist or can I use the tone generator in AECS3 to create this sound, and if so does anyone know the settings?
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#2 Kokosing

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Posted 21 October 2009 - 02:04 PM

I've been asked send some work I've created directly to a broadcaster and amongst the specs is the following sentence:

"5 seconds of EBU colour bars (100.0.75.0) and accompanying 0dBm (-18dBfs) stereo identified audio tone @ 1 KHz
• sine."

I've found some tone bars on the internet, but have no idea what this tone is. Does a sound file exist or can I use the tone generator in AECS3 to create this sound, and if so does anyone know the settings?


I don't have AE, so I don't know how to setup the generator. But there's nothing ambiguous about what they want: 0dB of 1KHz tone. I can upload the PAL bars and tone from FCP if you'd like. And I do mean the full field PAL bars. For some reason FCP used to use NTSC bars in place of the PAL one.

W

Edited by Kokosing, 21 October 2009 - 02:05 PM.


#3 zook

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Posted 21 October 2009 - 02:44 PM

Thanks for the advice. I think the tone bars I've got are OK (can you generate these from within FCP?), and following your post I generated a 1kHz tone @ 0db from within Soundtrack.
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#4 Kokosing

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Posted 21 October 2009 - 03:09 PM

Thanks for the advice. I think the tone bars I've got are OK (can you generate these from within FCP?), and following your post I generated a 1kHz tone @ 0db from within Soundtrack.


Good old soundtrack. I don't know if FCP has a tone generator. I seem to recall that AVID does. The bars and tone in FCP are media files that come with the app.

Glad you got it sorted.

W

#5 tcastudios

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Posted 21 October 2009 - 03:47 PM

Thanks for the advice. I think the tone bars I've got are OK (can you generate these from within FCP?), and following your post I generated a 1kHz tone @ 0db from within Soundtrack.


Just like to mention. 0dBm is the full scale level. Make sure you are printing -18dBfs, that is there must be 18dB of headroom.

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#6 graymachine

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Posted 21 October 2009 - 05:36 PM

The level of -18db is to emulate the headroom of analog. Analog can hit 0dB with some wiggle room above that. How hard you hit 0 in the analog world is subjective and depends on the size of your balls. Some hit it hard, some stay out of the red zone.

But, with digital, above 0dB turns into complete digital gibberish. So, we emulate analog 0dB to somewhere safely below 0dB. This is unique to each facility, and I consider -18dB to a bit of a wuss out, but many use that. Some use -12 or -15.

In AE, just apply the "Tone" effect to a layer. Set all but one of the generators to 1000 Hz, and the rest to zero. Adjust the level so that it reads -18dB.

Keep in mind this is really only useful as a reference if you are delivering audio that peaks around the same spot. That's the whole point. The audio reference says "here's where my audio level is", and the engineer playing the tape will adjust levels to the tone level. The program content should be in the same level.

(thank you for humoring me and letting me use my audio engineering degree for 5 minutes)

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#7 tcastudios

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Posted 21 October 2009 - 09:48 PM

The -18dBfs pilot tone and the level of the content has no connection.
The pilot tone is a pure machine reference and happens to be
what EBU accept as headroom for transients/keeping modulation safe.

Should you deliver your material with a loudness average at -18
you most likely will have to redo it.
A regular AR track, think Tom Petty, would read a loudness average
at around -14dBVU ( 160ms release time)

But, As from Red Hot Chili Peppar and Ramstein (-12 to -9) all is lost anyway :)

Cheers
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#8 zook

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Posted 22 October 2009 - 03:53 PM

Erm, I don't have a flippin' clue what you guys are talking about.

Does this mean my aif of a 1kHz tone from Soundtrack can't be used? Do I need to alter this in some way shape or form?

Make sure you are printing -18dBfs, that is there must be 18dB of headroom.


Pardon? How do I know this? Printing? eh?
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#9 tcastudios

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Posted 22 October 2009 - 07:15 PM

Printing is what you put on your final master.
The 1kHz tone should be -18dBfs.
So if you render out the tone from in example Soundtrack
just make sure the output meter reads -18dBfs.

Once in you final master nothing should be done to it
or it will not be correct.

Cheers
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#10 zook

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Posted 24 October 2009 - 08:20 AM

Thanks for the help!
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