Another option is to remove existing drywall and fill the space between the studs with standard pink insulation or Rockwool stone wool batt insulation, which is denser and offers excellent sound ...

If the ceiling already has drywall, it might be worth the effort to remove it and add insulation. This also gives lets you ...

As windows and doors are often much thinner than walls, you may want to use weather stripping to seal any cracks to help prevent sound from entering or leaving. You can also add an extra drywall ...