ITU-R BS.1770-1 Loudness, Free VST Plugin

i am erikd wrote on 1/27/2012, 7:03 AM

When submitting digital content for broadcast delivery these days I'm having to comply with the ITU-R BS.1770-1 audio loudness standard. If you enjoy learning more about this kind of mind numbing information you can read about it here:

http://tech.ebu.ch/docs/r/r128.pdf

and here:

http://en.wikipedia.org/wiki/Loudness_war

Many of you already know much more about how this all works than I do as I am largely just in the compliance phase. If they accept the content, I'm happy to move on without fully understanding all the details and intricacies.

There are many solutions out there to monitor for -23 LKFS or 0 LU (depending on your personal preference) and some are quite expensive. I came across this free VST plugin that works in Vegas9e (Maybe someone else can verify if it works OK in V10 or V11) and it seems to do the trick for me so far. It can be set to measure LKFS or LU; I prefer LU but these are only two different ways of expressing the same measurement.

If you are interested, go to the link and click on the tab AC-R128. Again, it's a free VST plugin that works fine in Vegas.

https://www.audiocation.de/en/plugin

Erik

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Comments

musicvid10 wrote on 7/27/2012, 6:35 PM

Though not an "idiot sheet," this overview provided by the EBU-R128 folks gives a clear basic explanation of what's at work. With a few minor exceptions, the same applies to those using ATSC A/85 in the US.
http://tech.ebu.ch/docs/techreview/trev_2010-Q3_loudness_Camerer.pdf

Since finding the Toneboosters plugins, I haven't had need for anything else (although I still keep on top of developments with Nugen).

wwjd wrote on 7/31/2012, 2:51 PM

found something of a basics guidelines. seems to jive with everything else I have seen and read:

Analog (old school) audio, cassettes, Betacam SP, S-VHS, VHS - peak level is 0dB (but can occasionally exceed to +1 to +3dB and still sounds okay to most listeners)

MiniDV/DVCAM/Final Cut Pro's meters - nominal peak level is -12dB - this means that your audio levels should not exceed higher than -12dB on peaks. You still have 12dB of headroom in your digital signal for peaks, but once you exceed -12dB peak level, you run the risk of distorting analog sources that you may record to like VHS or Betacam SP.

The rest of the professional digital audio world, Betacam SX, DigiBeta, HD, DVC Pro and variants peak level is -20dB. The professional audio and video world, through the Society of Television and Motion Picture Engineers (SMPTE), decided many years ago that -20dB was fine as a standard peak level. Over the years, it has evolved to some different variations, including -18dB and -14dB, but most professional equipment still is marked for a nominal peak level of -20dB. In theatrical sound systems, capable of huge dynamic range, you may need -20dB of headroom so that explosions and other dynamic sound effects can playback without distortion.

musicvid10 wrote on 7/31/2012, 4:11 PM

dbM. dBV, dBu, dBa, dBFS, dBRMS, dBVU, dBPPM, dBTP, dBSPL, dBPA, dBA,B,C, dBLU, dBLK

Apples and oranges and bananas and pears and grapes and melon and kiwi and pomegranates.
If you're thinking fruit salad about now, you're getting it. No relation at all between dB references and standards without context, and then often very little . . .

ChristoC wrote on 7/31/2012, 5:57 PM

as musicvid points out, 'dB' must be accompanied by some other scale reference parameter; 'dB' by itself is just a ratio which can only be used to compare 2 levels within the same scale.

Under these new rules we are still allowed to peak to close to 0dBfs (full scale on a digital peak meter) occasionally (for the odd ultraviolence etc), its just that we can't be there all the time.... the new metering uses a different scale paradigm (Loudness Units) which is really difficult (i.e. impossible) to relate to the usual old-school Analog VU or Digital Peak meter scales.

wwjd wrote on 7/31/2012, 7:00 PM

but to put it all so simply:

digital peak meters go red and distort at or past zero.
so, with music sitting around -8 to -20, TV Movies and all the rest have SOME very basic guidelines... like "Don't go above zero" , and general common sense will keep most things similar, so I was just asking what "similar" is for movies and TV?

I'll just load up a bunch of movies and TV shows and come up with my own averages. Or read those 60 page PDFs.... and in the then they will say: Sit around -20 to -12 and you'll be fine :)

musicvid10 wrote on 8/1/2012, 1:51 AM

" . . . so I was just asking what "similar" is for movies and TV?"

* EBU R68 is used in most European countries, specifying +18 dBu at 0 dBFS

;?)

mudsmith wrote on 8/1/2012, 4:16 PM

To clarify a couple of things which are being confused:

1)When the US TV standards say -20dbfs, they are talking about POL (program operating level), which does not really mean operating level, but the level at which you record tone. In digital, this automatically means that you have 20db of headroom, and it also means that your analogue output will be +4dbm/dbu with a tone at -20dbfs........which would give you a reading of "0" on the old analogue VU meters in use in the U.S. There are plenty of other digital "standard" operating levels (and thus headroom available) throughout the audio industry, but the -20dbfs is now standard for U.S. TV.

2)Using the standard above when recording audio to a DigiBeta machine 10 years ago, this means that you would want to see your average peaks hitting -12 to -10, given the ballistics of the meters involved. This allowed headroom throughout the various broadcast chains involved........When sending a Digibeta master in for DVD or similar, you might very well apply more mastering processing and higher average levels, but such a tape should be rejected by broadcasters .

3)This rough reference for "average peaks" as described above using the meters on a DigiBeta is really not that far off, as far as I can tell, from the new standards, but the new standards are using a different scale that measures the new concept of Loudness as opposed to level with some ballistics overlay as per the Sony decks. For that new scale, the average peaks are supposed to be around -24 for a mixed program........but the absolute, real peaks are not supposed to exceed -2dbfs.

......Given that, I really don't know what the best software or hardware metering solution is now to get into compliance with the new standards.......has anyone used the new Waves package?