I was talking to my friend Ian Stewart (http://ianstewartmusic.us/blog) recently and we discovered that we had both been playing around with the same idea which was to find a solution to calculate Replay Gain measurements to predict how much (and how) Spotify would adjust the loudness levels of a song.
The "word on the street" (meaning online, forums and Facebook groups) is that "all streaming services uses LUFS values to normalize to". As of this writing, that is actually
There's quite a bit of inaccurate information out there... one of those is how online streaming platforms are loudness normalizing the music playback. NUGEN Audio has published this fine guide. But they're also spreading the "inaccuracy". Those LUFS values do indeed give us a great idea of the "ballpark" that those services are at regarding loudness normalization, but in the "business of accuracy" that we audio engineers, and especially mastering engineers, are in, then using