Where does music come from that streams?

If I was creating my own streaming company, would I reproduce songs from a CD or from a record? So when I listen to my streaming source, qobuz, where do they get the music I listen to? Does the music come from master tapes? Well that would seem to be a pretty good place to get it

Sometimes I wonder, a particular song on qobuz doesn’t sound very good and I know I’ve heard it better in the past. And most stuff sounds pretty good and comparable to other sources.