I basically always leave those settings completely flat, simply because I want the sound coming out of my speakers to be as 'honest' as possible. Also, I'm generally paranoid about touching those settings, since equalizers are filters, and literally all filters produce ringing artefacts in one form or another, often resulting in smudged transients.
I should point out that the vast majority of listeners in general cannot tell the difference between the different format, to the point where I would argue it's largely a pointless skill. No, the actual reason for having a lossless master around to copy from, is because MP3 artefacts do get audible when the audio is resampled recursively, the same way the grunge of magnetic tape becomes more visible every time video gets re-recorded. Keep in mind the MP3 format was engineered to specifically filter out the information the human ear doesn't pay attention to
never again, wonder if there's possibility of re downloading all my juno flacs in wav instead, there's something weird going on with certain flacs and noise floor/dampening very hard to explain but wav sounds more true, more organic, less digital and more powerful & punchy with better control on dynamics.
