Yup....
The differences can be subtle like you said, and most of those million dollar studio pros would also say the same thing, and that you pay a lot to gain 5%-10% in quality....BUT...when you consider that for all the gear in entire audio chains....those 5%-10% increases can add up and that's how the million dollar studios can consistently put out quality audio (music tastes aside).
At the home rec level...we can sometimes hit on a really great audio chain combination that is not very expensive, but it's not always the case across the board, all the time....IOW, it can be pot luck...and also highly dependent on the users.
The pros simply invest a lot of money in order to take the gear quality out of the equation...or maybe better said, to make sure the quality is never going to be in question.
So...to answer the OP....yes, the converter can make a difference, but it will be subtle, especially if you are using a straight converter VS some of the all-in-one boxes which can affect the signal a bit more.
So the quality of the preamp will get preserved for the most part.....of course, everything else in the chain will also be in play too.