This is a little off topic, but this was posted on /r/headphones the other day and it was a really interesting watch. Compares streaming services and the quality they offer in an A / B test with the master track.
Which STREAMING SERVICE SOUNDS the BEST?:
Silly test - he should asked the owner of the record label if they submitted a different master to Apple iTunes maybe cause of "Mastered for iTunes".
If you look at the waveform of his master the louder part seems to be very loud (not saying brickwalled) and the Apple Music one is not as loud as his master by far on these parts. - So either they did a completely different master or at least reworked his submitted project before handing it over to Apple.
<edit> And as this video shows, he was doing his projects only in 48 kHz until recently while at least 96 is standard since looong time:
And other Videos show he has many old-school opinions. (tending to compressing and limiting)</edit>
It's logical that the whole subtracting one Waveform from the other and listen to differences only is giving comparable results you can work with, when both Waveforms should be the same. - But that isn't if the master is completely different....
..and he never says if it sounds better or not - only different.
<Another Edit>
My ranking of streaming Services Audio quality
Total number 1: Qobuz Sublime+
--big gap-
2. Tidal Masters with MQA Hardware unfold
3. Tidal Masters with Software unfold
--gap--
4. Qobuz Hifi + Tidal Hifi + Deezer Elite
5. (sometimes 3 1/2) Apple Music (Uses often different Masters and these ones are often even better than the once at place 4)
6. Qobuz Premium + Deezer Premium+
7. Spotify, Amazon Music unlimited, Google Play Music (or whatever it is called now)
8. Soundcloud, Pandora and others
9. Youtube