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ptfigg
08-28-2014, 07:42 AM
I've written about this on going issue regarding loudness compliance and the absence of consistency in the Podcasting space. Besides most producers lacking the technical skills that are needed to properly address these issues, there are misconceptions that complicate matters further.

For example, your standard PPM (Peak) Meter is a useless indicator for measuring perceived, average loudness. The sole purpose of a PPM Meter is to monitor Peak Amplitude to avoid overload (clipping). Two pieces of audio can have the same exact peak ceiling, while one is perceptually "louder" than the other.

Of course your Peak Ceiling and sufficient headroom is part of the well produced audio equation, especially when the producer is distributing MP3 files derived from lossless masters, like WAV and AIFF.

Anyway, I produced a tutorial that demonstrates a sort of in the box "off-line" workflow that producers can use to establish both Program Loudness and Peak Ceiling consistency. I'm happy to elaborate on any questions that you might have.

A few Notes:

[-- The workflow is not limited to the Pro Tools environment.

[-- You don't need the TC Electronic Loudness Meter for off-line clip measurement. There are free options available.

[- You will eventually need to learn how to use a Loudness Meter. Again, I'm willing to help.

The workflow was inspired by the documentation in the following article:

"Managing Audio Loudness Across Multiple Platforms" (http://www.tvtechnology.com/audio-etc./0193/managing-audio-loudness-across-multiple-platforms/267334) (Thomas Lund), TVTechnology/Broadcast Engineering, January 2013. I did slightly alter the Limiting recommendation.

In a case you are wondering why the Limiting stage is not located at the very end of the process, good observation. The answer to this is simple math. If after viewing the video you are confused about the placement of the limiter, refer back to this math, and you will see that the limiter is in fact doing it's job:

If you start off with -9.5 ... and then add 8 ... you will always get -1.5.

In essence this will be the ultimate Peak Ceiling after processing. Of course it's possible that it may be lower, which is fine. It all depends on the attributes of the input file. Bottom line is the processing workflow will establish -1.5 dBTP as the ultimate ceiling, and -16.0 LUFS Program Loudness.

Lastly, and just like any other method of processing audio - the condition of the source will impact the quality of the output. This process may actually make things worse for you, especially is you are starting off with poorly produced low level audio and bumping things up to meet the recommended targets.

Let me finish up by saying that auphonic (https://auphonic.com) may be worth checking out if you find these manual methods to be too complex.

Here's the screencast: Loudness Normalization Tutorial (http://f-video.s3.amazonaws.com/Loudness-Normalization.mp4)

-paul.

Donovan
08-28-2014, 03:37 PM
Good and informative video. Thanks. :)

BradShoemaker
08-29-2014, 04:07 AM
For those with Adobe Audition, the TC Electronic Loudness Meter is included. It can be found under EFFECTS > SPECIAL > LOUDNESS RADAR METER.

The only issue is, you can't offline it... meaning you have to real time play your audio to get the reading, unlike Pro Tools.

rudyengels
08-29-2014, 04:32 AM
I'm going to file this for future reference. I don't understand everything but see what the purpose is. Thanks for the info!

docizzen
08-29-2014, 08:41 AM
Awesome tut ptfigg! Thanks so much for sharing you knowledge and expertise. Well done!

ptfigg
08-29-2014, 09:42 AM
For those with Adobe Audition, the TC Electronic Loudness Meter is included. It can be found under EFFECTS > SPECIAL > LOUDNESS RADAR METER.

The only issue is, you can't offline it... meaning you have to real time play your audio to get the reading, unlike Pro Tools.

A fews additional points:

[-- It's only included in the CC version of Audition

[-- There is no clear True Peak indicator. In other words there is no exact reference to a numerical value. There is only a light that flashes when the signal passes the defined True Peak Ceiling

[-- There are no Statistics.

The Audition Amplitude Statistics feature will supplement what the meter lacks. You do need to run this off-line.

-paul.

ptfigg
08-29-2014, 09:44 AM
Good and informative video. Thanks. :)


I'm going to file this for future reference. I don't understand everything but see what the purpose is. Thanks for the info!


Awesome tut ptfigg! Thanks so much for sharing you knowledge and expertise. Well done!

You're welcome, everyone ...

-paul.