Meeting Topic: TV Loudness: Be ready for the next decade
Moderator Name: Mark Edwards
Speaker Name: Jean Paul Moerman, Salzbrenner Stagetec GmbH
Meeting Location: JMC Academy, South Melbourne
Jean Paul Moerman of Salzbrenner Stagetec gave us an overview of the topic "TV Loudness".
This has always been a sensitive topic, but since the evolution of TV to digital systems the apparent problem has intensified.
Jean Paul described the new metering system developed by the European Broadcasting Union to better measure program "loudness" than the PPMs, QPPMs, and peak-reading meters now commonly used in Europe.
He described a project he ran when Head of Sound at Flemish TV, VRT — the Belgian National Broadcaster, to improve the loudness consistency and reduce viewer complaints.
This involved a 4-step process of 1)Standardizing metering and meter scaling using metering based on ITU-R-BS.1170 algorithm, 2)Appropriate and standard monitoring levels at all mixing points, 3)Modulation and processing rules, and 4) The Operators' ears (somebody is monitoring and controlling levels). Implementation of the plan, which also involved significant operator training, reduced viewer complaints about the sound (which had previously been 75% of all viewer complaints) to 0.7% of the previous numbers.
Jean Paul also walked us through a typical Loudness Consultancy which he would now do — in this case RTM the Malaysian National Broadcaster in Kuala Lumpur.
He then described the loudness metering system based on the BS.1170 algorithm on which both the EBU and ATSC (US) loudness metering systems are based. He commented that the now largely abandoned VU meter was a "pretty good" loudness meter, but had some limitations - which meters to the new EBU R128 standard address.
He also went into significant depth on the importance of consistent and appropriate monitoring levels for operators who are making mixing decisions. He explained that mixing at elevated levels compared to the average viewer's listening level results in a mix with too high a dynamic range for the viewer, such that the dialog is unintelligible or the foreground effects are uncomfortably loud. The European broadcasters' recommended monitoring level is 77dBSPL per channel, and his own measurements of viewer listening levels indicate this to be a valid monitoring level to generate mixes that translate well to viewers' lounge rooms.
The talk was peppered with audio examples, and provided a lot of information in an easily digestible form.
A lively question and answer session followed, and we all left the meeting with a better understanding of the challenges of maintaining consistency in TV audio loudness, and the tools that are coming into to play to meet those challenges.
Written By: Peter Smerdon
