Standardizing Audio Levels for Broadcasting

Thursday, 02 February 2012 22:36

Written by Resti Reyes. Jr.

If you have ever wondered why you have to keep adjusting the volume level on your TV every time you switch channels, or even when a commercial break comes up, fret no more. You are not alone. In fact, it is a terrible malady that has plagued consumers all over the world ever since the dawn of broadcasting.

I used to think that radio and television station owners and operators were just being too eager to please their advertisers and so they would pump up the volume at every commercial break. It was a dumb idea of course. If it worked in the early days and got people’s attention – back in the days before the invention of the remote control, then the opposite is what happens today. If anything, the sudden surge in loudness prompts every normal person with reasonably functioning eardrums, to instantly grab the remote and switch channels. It is easier than fumbling with the button that tones down the volume because that process takes a few seconds to achieve the objective, and it is not always easy to find the tiny “mute” button on a remote control that has more buttons than a qwerty keyboard.

So what gives? Why can’t broadcasters keep their audio levels, well… level? It’s such a simple thing, right? I am sure they are just as irritated by it when they watch TV at home. Well, as it turns out, it is much more complicated than we have ever thought.

Anyway, a couple of weeks ago, The ITU (International Telecommunications Union) received an Emmy Award from the US National Academy of Television Arts & Sciences at the 2012 Consumer Electronics Show in Las Vegas for the “Standardization of Loudness Metering for Use in Broadcast Audio”.

What does this mean?

The annual Technology and Engineering Emmy Award recognized the ground-breaking work on the worldwide standardization of loudness metering for use in broadcast audio, which the Academy considered as outstanding and showing excellence in engineering creativity. The work of figuring that out took over ten years. And what is now known as “ITU-R Recommendation BS.1770” – or, “Algorithms to measure audio program loudness and true-peak audio level” is the result of efforts of many specialists from different countries.The standard was finalized during the study period under the leadership of the European Broadcasting Union. The pertinent algorithm and the agreed parameters are now contained in the ITU-R Recommendation approved by ITU member states, giving worldwide guidance on loudness metering.

Who knew, right?

The report says, “The ITU-R Recommendation BS.1770 on Loudness Metering in Audio Broadcasting will improve the experience of watching television for viewers worldwide as they will no longer have to adjust the volume on their sets while switching channels or watching commercials. There are many applications where it is necessary to measure and control the perceived ‘loudness’ of audio signals,” said ChristophDosch, chairman of ITU-R Study Group, the group responsible for the report, and the one that is focused on broadcasting services.

Examples of this include television and radio broadcast applications where the nature and content of the audio material changes frequently. In these applications the audio content can continually switch between music, speech and sound effects, or some combination of these. It can also change between various audio or audio-visual sources, for example in international program exchange. Such changes in the content of the program material can result in significant changes in subjective loudness, and the new standard on loudness metering will make it easier for television viewers.

Don’t forget that the matter of subjective loudness is also of great importance to the music industry where dynamic processing is commonly used to maximize the perceived loudness of a music recording. Listen up, record execs.

For whatever it is worth, we want to thank the Academy… blah, blah, blah…

In the meantime, thank heavens for the remote control. It’s been the best thing since the sliced bread commercial.

-- with apologies to the concerned advertisers who may have suffered awareness level losses due to the now-prevalent habit of viewers zapping their commercials, prompted no doubt by the exceedingly loud audio levels during the commercial breaks.