What audio levels do television news channels use? There are long-established standards for television production, but what levels are observed by a typical home consumer? Using FFMPEG's "volumedetect" feature we can get some estimates using:
ffmpeg -i ./VIDEO.mp4 -filter:a volumedetect -f null /dev/null
Here are the results for a randomly selected CNN broadcast from Dec. 1, 2020 ("volumedetect" only displays the first few entries of the histogram):
n_samples: 351303680 mean_volume: -32.3 dB max_volume: -4.7 dB histogram_4db: 13 histogram_5db: 16 histogram_6db: 27 histogram_7db: 73 histogram_8db: 272 histogram_9db: 668 histogram_10db: 1558 histogram_11db: 3899 histogram_12db: 7676 histogram_13db: 16404 histogram_14db: 35266 histogram_15db: 69792 histogram_16db: 130424 histogram_17db: 232799
The results for a BBC News broadcast the same day:
n_samples: 178550784 mean_volume: -26.4 dB max_volume: -5.5 dB histogram_5db: 6 histogram_6db: 62 histogram_7db: 799 histogram_8db: 5850 histogram_9db: 29804 histogram_10db: 83199 histogram_11db: 177939
The results for a Fox News broadcast that day:
n_samples: 351348736 mean_volume: -31.9 dB max_volume: -7.3 dB histogram_7db: 2 histogram_8db: 62 histogram_9db: 233 histogram_10db: 710 histogram_11db: 1474 histogram_12db: 3155 histogram_13db: 8520 histogram_14db: 19879 histogram_15db: 42304 histogram_16db: 86969 histogram_17db: 167447 histogram_18db: 309361
The results for an MSNBC broadcast that day:
n_samples: 351356928 mean_volume: -32.8 dB max_volume: -8.3 dB histogram_8db: 25 histogram_9db: 35 histogram_10db: 68 histogram_11db: 243 histogram_12db: 662 histogram_13db: 2318 histogram_14db: 5942 histogram_15db: 14843 histogram_16db: 33365 histogram_17db: 66772 histogram_18db: 135605 histogram_19db: 297055
All three US channels are fairly in sync with one another, while BBC News is slightly louder, though it isn't clear whether that is just the one randomly selected broadcast or a more consistent pattern.