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Ask the experts by Jon Schorah, Creative Director NUGEN Audio. N ow that loudness is a mandatory requirement in the United States, Europe, and much of the rest of the world, it’s not so much a question of when organizations will begin to comply, but how. Now the standards are in place, what happens now if my work is not compliant? There are varying repercussions for noncompliance, depending where you work and in which segment of the industry. For the post-production engineer, if you are not required to deliver loudness-compliant audio, then your main concerns would be international compatibility and downstream correction. If you produce sound for broadcast in a compliant region, then your noncompliant work will either be rejected outright or corrected in a manner beyond your creative control. Because the majority of audio is now moving toward compliance, even if your work makes it to broadcast in its original form, it likely will not compare well to compliant material being broadcast alongside it. If you are required to submit compliant material, a near fail might simply result in correction at ingest, but rejections — along with their associated fees and delays as you rework your submission — are becoming more commonplace. Broadcasters are in a similar situation. In fact, for broadcasters, voluntary compliance should be a very serious consideration. Anecdotal evidence suggests compliance pays dividends, even in a commercially competitive environment. To the extent that they will choose to stay with a commercial break rather than surfing, consumers genuinely prefer a loudness-compliant channel. Where compliance is required by legislation, then noncompliance can ultimately result in heavy fines. The drop in loudness-related complaints in the wake of loudness regulation would suggest that, ultimately, the consumer prefers compliant material regardless of legal considerations. Where in the broadcast pipeline should loudness be addressed? From a technical perspective, there are many places in the audio path that loudness can be addressed, namely playout, ingest, and post-production. a. Control During Playout The first approach is playout processing, a scenario in which real- time processors continuously measure and adjust the station output to ensure loudness compliance. Playout processing delivers a technically compliant broadcast, but this method has its drawbacks. For example, in extreme situations, a particularly loud commercial that has been brought into line with real-time processing can actually cause a loudness problem if the programming that follows it is relatively soft. One way to refine this approach is to bypass processing when broadcasting compliant material. Rather than processing the entire broadcast, switch processing on only when material is noncompliant or of unknown origin . The Federal Communications Commission (FCC) in the United States strongly discourages the use of live audio processing to meet loudness requirements. b. Control at Ingest A better approach is to ensure compliance at the server level during ingest. This technique can be adapted readily to a modern, file-based environment and works well even with automated batch processing. The downside is that the method can break down during the transition from feature film to television, when loudness range reduction (LRA) requirements come into play. Processing can often change the nature of the sound considerably and can also introduce issues with dialog clarity. That said, a file-based loudness solution can often deliver perfectly acceptable results in cases where the original resources are not available or budgets prohibit anything more involved. c. Control During Post By far the best solution — and the one that offers the most creative freedom — is to make a mix loudness-compliant during post-production. This approach integrates loudness into the creative process so that it can be considered alongside other audio variables, ultimately producing audio that satisfies both the consumer and the creative professional. How can loudness be handled at Ingest? In a file-based environment, checking and adjusting audio for loudness compliance can be readily addressed at ingest using batch processing, which can assess and check files for compliance and even automatically fix audio that is close to target. These corrections are best achieved by a simple loudness offset (with true-peak limiting) that produces compliant material without “treating” the audio with processes that introduce audible artifacts. If material falls outside acceptable limits for the offset approach, then some dynamic scaling (LRA reduction) can also be helpful, although this approach should be used with caution because it encroaches into the creative sphere and might be better suited for post-production. How does loudness fit into the post production workflow? The best way to employ this approach is to find a loudness-control solution built for the post-production environment, one that offers intuitive loudness tools for audio editors including real-time metering, offline correction, and loudness-compliant limiting. Visual Loudness Meters Clear, intuitive loudness metering is the key to delivering high-quality, loudness- compliant audio. Current standards hold the potential for increased dynamic range and contrast. Loudness recommendations are based on a loudness scale designed to correspond to the human ear. With a visual meter, editors can keep an eye on the meter and loudness profile while relying on their trained ears to make most of the decisions. 48 | TV-BAY MAGAZINE: ISSUE 77 MAY 2013 TV-BAY077MAY13.indd 48 02/05/2013 21:18