For what it's worth, I have a lot of old jazz (vintage 1930's) in my collection. The digital remasters that came from 78rpm suck. Every once in a while, they manage to dig up the metal stamping parts, which yield radically better fidelity. Still, it wasn't until the 1950's that recordings had anything resembling modern high fidelity. To my ear, some of the jazz greats of the 1930's recording music in the 1950's, with master tapes redigitized in the 2000's and issued on CD, are as good as it gets.