Also a number of different specifications for how it is measured. https://auphonic.com/blog/2012/08/02/loudness-measurement-and-normalization-ebu-r128-calm-act

Also a number of different specifications for how it is measured. https://auphonic.com/blog/2012/08/02/loudness-measurement-and-normalization-ebu-r128-calm-act/ https://auphonic.com/blog/2012/08/02/loudness-measurement-an...