For the last few years, the Audio Engineering Society has done much work in the areas of loudness and dialogue intelligibility.
Many feel these topics are relevant mostly to the video industry, but radio and audio streaming must focus on them as well.
Radio stations are producing more video to stream and post. Stations are also streaming their audio. With broadcasters seeking to monetize streams separately from their OTA product, programmatic ad networks are injecting commercials to replace the original spots.
A key requirement is that the loudness level — measured in LUFS or LKFS — has to be equal to that of the program content. If it is not, your audience will start riding the volume knob. And when a listener goes to adjust volume, it is just as easy for them to change station or turn it off. So it’s important to manage loudness consistency.
Many recording studios are checking loudness as part of their quality assurance procedures. This is becoming more of an issue now that states like California are adopting CALM acts to regulate loudness of commercials, not only for broadcast but over the web.
Yes this can mean videos posted by broadcasters, most of which have pre-roll or mid-roll commercials. For best presentation, set the loudness level of your content to equal that of the commercials. There are many loudness meters available, and some are free to download. Personally, I like the Orban and Youlean meters.
Dialogue intelligibility is also important for audio of broadcasts or streams. It’s important that the anchor audio is understandable and not overtaken by surrounding sound, especially since people are trying to mix for immersive and not thinking stereo or mono.
Dynamic Range Control will aid audience comprehension. Many are mixing video for cinematic presentations but forgetting about other uses (e.g. home and mobile). The mixers should trust their ears and listen with the same equipment as the intended audience.
For the audience, I suggest using a good 5.1 audio system with a center channel or a sound bar that has a center channel. This is important for video as well as audio services like radio and audio-only streams.
The goal of a producer or distributor should be to deliver high-quality audio that can be understood.
Recommended resources include the Audio Engineering Society’s Technical Documents TD-1008 Recommendations for Loudness of Internet Audio Streaming and On-Demand Distribution (which has been elevated to standard AES77 Recommended Practice Loudness Guidelines for Internet Audio Streaming and On-Demand Distribution) and TD-1009 Improving Dialogue Intelligibility in Media.
These documents were published by the AES Technical Committee for Broadcast and Online Delivery. Each was created by consensus, which means every committee member came to agreement for everything written. These documents are free to anyone for download, while the standards are available for purchase.
