Tube preamp, easy solution.The price of resolution I guess. When I moved into TOTL space, I kinda stopped listening to music from when I was a kid, as it sounded terrible. Had to add some harmonics with tubes to smooth it out a bit. A pity this isn't really possible right now with Audeze ribbon.
One could get a Schiit Freya just to get started.
Or use the preamp function of most high end tube amps like Wa33