I should have mentioned that I listen to CD, Vinyl, and some streaming - in that order of frequency (no pun intended). Sorry about that. So an app or program wouldn't be a complete solution. I am seeking a hardware solution.
Looks like some piece of Schiit gear (another obvious and well worn pun) is a consensus so far. I didn't know they had a trial period.
I think I'll head back to their website.
I had an ADC equalizer way back in 1980-ish. I don't recall how effective it was but then again it was in a pretty low end system. I'm hoping that the gear available today is better and more suited to the job at hand.

