We have a square-shaped, corner room that we use as a piano room. The room has doorways into both adjacent interior spaces. One doorway has large French doors with a transom. The other is just open - no doors.
We're remodeling by moving the French doors to the open doorway and closing off where the French doors currently are. The sound of the piano carries quite a bit into the adjacent spaces. Moving the doors and closing off the wall will help with that.
I'm wondering if it'd be worthwhile to also add sound-dampening insulation to fill the space in the new section of the wall. That would mean about 30-40% of the wall would have sound-dampening insulation. Or would it be insignificant to insulate only part of a wall?