Room acoustic treatment with a piano and a closet

Hi,

I'm going to buy some new monitors for my room, but I want to fix some acoustic issues in it first.



In the back of my room (in front of the monitors) there is a big closet that covers almost the whole wall. When i'm thinking about the right treatment should i consider this closet as a "wall" (decrease the actual dimension)? absorbers on the closet doors should be a good solution?



Second, to the right side of my listening position there is a piano. What can i do with that if any treatment is needed at all?



Thanks!

Room acoustic treatment with a piano and a closet