Of the stadiums listed, I've been to MI (against OSU), OSU (against MI), WI, and IA
Michigan is (by far) the "least loud" of the four - part of it has to do with wide stadium bowl design (there is no "second deck") and part of it is because Michigan fans are known for sitting on their hands. The only reason the venue may generate any loudness is because they have 100k+ fans in the stands.
Of the others, I would say OSU>IA>WI (but it is pretty close overall between the three)