Hi
You do have the ability to change the 'characteristic' of a wall, or part of a wall.
It may not have ''fibreglass absorber'' for example, but if you know the properties of the item you could probably enter it manually.
NB
Simon - I'm getting on great with your bass absorbers. They are great.
In combination with acoustic panels on the wall, my room is greatly improved.
Of course, it could never be as good as a 'very good room' is automatically, but it's a lot better than it previously was, and that is all that counts.
Thanks again.