There seems to be quite a lot of dsp based room correction for digital but what are some analog solutions for vinyl systems?
There's a lot for digital because digital sounds so awful people are constantly incessantly running around looking for excuses and ways to make it sound slightly less awful. Oh wait, what's that? People are holding onto and loving and cherishing their digital gear for decades like they do with analog? No, that's not happening.
Another factor, its the numbers and graphs and stuff that sucks people into digital. Because it sure ain't the sound! Oh wait, what's that? The whole world is so convinced digital sounds good that when a record manages to sound pretty good they say it sounds digitally? No. They say digital sounds analog.
So anyway here's the analog solution to dsp with vinyl: adjust your VTA, adjust your VTF, adjust your speaker placement, move your subs around, move your listening chair around, try various acoustical treatments. If you were mislead into buying wire or anything else based on the band-aid (aka "system matching") approach, change them.
Not being smart. But if you are you will. This is also by the way the approach to take with digital. I mean, if you want to try against the odds to make it sound good, and not just look good on a graph.